JP7488776B2 - Bridge resonance detection method, resonance detection device, and bridge resonance detection program - Google Patents

Description

This invention relates to a bridge resonance detection device that detects the resonance of a bridge over which a moving object moves, and to the resonance detection device and bridge resonance detection program.

When large amplitude vibrations occur due to resonance in high-speed railway bridges, the amount of bridge deflection, crack progression, and fatigue become major problems in terms of maintenance. This occurs when the regular excitation frequency caused by the length of the train cars matches the bridge's natural frequency. There are high-speed railway lines where the amount of deflection due to resonance has actually exceeded the regulated value, causing trains to operate at a slower pace, so it is necessary to detect resonant bridges as soon as possible and take measures. Resonance can occur suddenly at some point after service begins, and measurements from the ground alone can result in normal operation while the train is in a resonant state. So far, a method has been proposed to detect bridges where resonance has occurred from a traveling commercial vehicle by using the vertical acceleration above the floor of the front and rear cars of a running train.

A conventional bridge dynamic response evaluation method (hereinafter referred to as Prior Art 1) measures the vertical acceleration of the leading and trailing vehicles traveling on a bridge, calculates an acceleration amplification factor based on the waveform features of the vertical acceleration of the leading and trailing vehicles, and calculates a bridge impact coefficient from the acceleration amplification factor (see, for example, Patent Document 1). A conventional bridge dynamic response evaluation method (hereinafter referred to as Prior Art 2) measures the vertical acceleration of all vehicles traveling on a bridge for each vehicle, calculates an individual vehicle amplification factor based on the waveform features of the vertical acceleration of each vehicle, and calculates a bridge impact coefficient from the individual vehicle amplification factor (see, for example, Patent Document 2). In Prior Arts 1 and 2, an index based on the vehicle acceleration response of a train traveling on the bridge is used to determine the bridge impact coefficient, and the dynamic response and the soundness of the bridge can be evaluated.

JP 2017-020172 A

JP 2017-020795 A

Conventional techniques 1 and 2 used the ratio of measurement data from the leading and trailing cars to avoid the effects of positional errors. However, in conventional techniques 1 and 2, detection accuracy could sometimes be reduced by vehicle vibration components. Furthermore, conventional techniques 1 and 2 were unable to identify vibration components specific to resonating bridges, so detection accuracy was reduced in areas with large track displacement other than the bridge's deflection components due to their influence. Furthermore, conventional techniques 1 and 2 targeted primary resonance, in which one wave of vibration is excited in the bridge each time a vehicle passes. However, conventional techniques 1 and 2 were unable to detect resonance in bridges with short spans, as primary resonance mainly occurs on bridges with span lengths of 30 m or more.

The objective of this invention is to provide a bridge resonance detection method and a resonance detection device and a bridge resonance detection program that can accurately detect the resonance of a short-span bridge based on vibration components specific to a resonant bridge.

The present invention solves the above problems by the means described below.
In addition, although the present invention will be described with reference to corresponding reference numerals, the present invention is not limited to this embodiment.
The invention of claim 1 is a bridge resonance detection method (#100) for detecting resonance of a bridge (B) over which a moving body (T) moves, as shown in Figures 1, 2, 7, 9 , 11, 13, 14, 18, 20 and ₂₁ , characterized in that it includes a resonance detection process (#140) for detecting Nth-order resonance (N _is an integer of 2 _or more) of a short-span bridge ( _B3 ) having a span length ( _Lb ) shorter than the vehicle length (Lc) of the vehicles (VF, VM, VL) that make up the moving body, based on the vertical vibration acceleration of the moving body measured from the moving _body side.

The invention of claim 2 is the bridge resonance detection method described in claim 1, characterized in that, as shown in Figures 2 and 13, the resonance detection process includes a process of detecting the resonance of the short-span bridge based on the measurement results of an acceleration measuring device (2) that measures the vertical vibration acceleration of the moving body from the moving body side.

The invention of claim 3 is the bridge resonance detection method described in claim 2, characterized in that the acceleration measuring device measures the vertical vibration acceleration in front of and behind the moving body, and the resonance detection process includes a process of detecting resonance of the short-span bridge based on the measurement results of the acceleration measuring device in front of the moving body and the measurement results of the acceleration measuring device in the rear of the moving body.

The invention of claim 4 is a bridge resonance detection method according to claim 3, characterized in that the acceleration measuring device measures the vertical vibration acceleration of the car bodies or bogies ( _T1 , _T2 ) of the leading car ( _VF ) and the trailing car ( _VL ) that make up the moving body.

The invention of claim 5 is a bridge resonance detection method according to any one of claims 2 to 4, characterized in that it includes a vibration component extraction step (#110) of extracting vibration components specific to a resonating bridge based on the measurement results of the acceleration measuring device, as shown in FIG. 11, and the vibration component extraction step includes a step of extracting vibrations whose main component is 1/N of the vehicle length of the vehicles that make up the moving body as the vibration component specific to the resonating bridge.

The invention of claim 6 is a bridge resonance detection method as set forth in claim 1, characterized in that, as shown in Figures 14, 20 and 21, the resonance detection step includes a step of detecting resonance of the short-span bridge based on the measurement results of a passage displacement measuring device (2A, 2B) that measures passage displacement on the bridge from the moving body side.

The invention of claim 7 is the bridge resonance detection method described in claim 6, characterized in that the passage displacement measuring device measures passage displacement in front of and behind the moving body, and the resonance detection process includes a process of detecting resonance of the short-span bridge based on the measurement results of the passage displacement measuring device in front of the moving body and the measurement results of the passage displacement measuring device behind the moving body.

The invention of claim 8 is the bridge resonance detection method according to claim 7, characterized in that the passage displacement measuring device measures passage displacement from a leading vehicle ( _VF ) and a trailing vehicle ( _VL ) that make up the moving body.

The invention of claim 9 is a bridge resonance detection method according to any one of claims 6 to 8, further comprising a vibration component extraction step (#110) of extracting vibration components specific to a resonating bridge based on the measurement results of the passageway displacement measuring device, as shown in FIG. 11, wherein the vibration component extraction step includes a step of extracting vibrations having 1/N of the vehicle length of the vehicles that make up the moving body as the vibration component specific to the resonating bridge.

The invention of claim 10 is a bridge resonance detection method as described in claim 5 or claim 9, which includes a vibration amplitude estimation process (#120) for estimating the amplitude of the vibration component specific to the resonating bridge measured in front of and behind the moving body, and a difference calculation process (#130) for calculating the difference in the amplitude of the vibration component specific to the resonating bridge measured in front of and behind the moving body , as shown in Figure 11, wherein the resonance detection process includes a process of detecting resonance of the short-span bridge based on the difference in the amplitude of the vibration component specific to the resonating bridge.

The invention of claim 11 is a resonance detection device for a bridge (B) that detects resonance of a bridge over which a moving body (T) moves, as shown in Figures 1 to 3, 7, 9, 11, 13 to 15, 18, and 20 to ₂₂ , characterized in that it is equipped with a resonance detection unit (4f) that detects Nth-order resonance (N _is an integer of 2 _or more) of a short-span bridge (B ₃ ) whose span length (L _b ) is shorter than the vehicle length (L _C ) of the vehicles (V F, V M, V L ) that make up the moving body, based on the vertical vibration acceleration of the moving body measured from the moving body side.

The invention of claim 12 is the bridge resonance detection device described in claim 11, characterized in that, as shown in Figures 2, 3, and 13, the resonance detection unit detects the resonance of the short-span bridge based on the measurement results of an acceleration measuring device that measures the vertical vibration acceleration of the moving body from the moving body side.

The invention of claim 13 is a bridge resonance detection device, characterized in that in the bridge resonance detection method described in claim 11, as shown in Figures 2, 14, 15, 18, and 20 to 22, the resonance detection unit detects resonance of the short-span bridge based on measurement results of a passage displacement measuring device (2A, 2B) that measures passage displacement on the bridge from the moving body side.

The invention of claim 14 is a bridge resonance detection program for detecting resonance of a bridge (B) over which a moving body (T) moves, as shown in Figures 1 to 3, 7, 9, 12, 13 to 15, 18, 20 and ₂₁ , characterized in that it causes a computer to execute a resonance detection procedure (S500) for detecting Nth-order resonance ( _N is an integer of 2 _or more ) of a short-span bridge (B ₃ ) having a span length (L _b ) shorter than the vehicle length (L _C ) of the vehicles (V F , V M , V L ) that make up the moving body, based on the vertical vibration acceleration of the moving body measured from the moving body side.

The invention of claim 15 is the bridge resonance detection program of claim 14, characterized in that the resonance detection procedure includes a procedure for detecting resonance of the short-span bridge based on the measurement results of an acceleration measuring device (2) that measures the vertical vibration acceleration of the moving body from the moving body side, as shown in Figures 2, 3, 12, and 13.

According to a sixteenth aspect of the present invention, there is provided a bridge resonance detection program as set forth in the fourteenth aspect, comprising the steps of:
The resonance detection procedure is a bridge resonance detection program characterized by including a procedure for detecting resonance of the short-span bridge based on the measurement results of a passage displacement measuring device (2A, 2B) that measures the passage displacement on the bridge from the moving body side.

This invention makes it possible to accurately detect the resonance of short-span bridges based on vibration components specific to resonant bridges.

1 is a schematic diagram of a moving object moving across a short-span bridge that is the object of detection by a bridge resonance detection device according to a first embodiment of the present invention. 1 is an overall view showing a bridge resonance detection system according to a first embodiment of the present invention; 1 is a schematic diagram showing a configuration of a bridge resonance detection system according to a first embodiment of the present invention; 1 is a configuration diagram of an acceleration measuring device of a bridge resonance detection system according to a first embodiment of the present invention. FIG. 2 is a schematic diagram of a data structure of a measurement data storage unit of an acceleration measuring device in the bridge resonance detection system according to the first embodiment of the present invention; FIG. 1 is a graph showing the time history response of a bridge deflection when a train passes at each train speed, where (A) to (E) are graphs showing the time history response of the deflection at each train speed. FIG. 1 is a schematic diagram of a resonant bridge model for theoretical analysis. 1 is a graph showing an example of dynamic response components at a moving load position of a resonating bridge. 1 is a schematic diagram for explaining the detection principle of a bridge resonance detection device according to a first embodiment of the present invention; FIG. 1 is a conceptual diagram for explaining a method for detecting resonance in a bridge according to a first embodiment of the present invention; (A) is a graph showing the vertical displacement at the center of a bridge span when a train passes; (B) is a graph showing the vertical acceleration of the vehicle body when passing over a bridge; (C) is a graph showing the result of applying filter processing and envelope processing to the vertical acceleration of the vehicle body when passing over a bridge after filter processing and envelope processing; and (D) is a graph showing the result of applying differential processing to the vertical acceleration of the vehicle body of the leading vehicle and the trailing vehicle after envelope processing. 1 is a process diagram for explaining a method for detecting resonance of a bridge according to a first embodiment of the present invention; 4 is a flowchart for explaining the operation of the bridge resonance detection device according to the first embodiment of the present invention. FIG. 11 is an overall view showing a bridge resonance detection system according to a second embodiment of the present invention; FIG. 11 is an overall view showing a bridge resonance detection system according to a third embodiment of the present invention. FIG. 11 is a schematic diagram showing a configuration of a bridge resonance detection system according to a third embodiment of the present invention. FIG. 11 is a schematic diagram of a track displacement measuring device of a bridge resonance detection system according to a third embodiment of the present invention. FIG. 13 is a schematic diagram showing a data structure of a measurement data storage unit in a track displacement measuring device of a bridge resonance detection system according to a third embodiment of the present invention. 13 is a schematic diagram for explaining the detection principle of a bridge resonance detection device according to a third embodiment of the present invention. FIG. 11 is a conceptual diagram for explaining a bridge resonance detection method according to a third embodiment of the present invention, in which (A) is a graph showing the vertical displacement at the center of a bridge span when a train passes, (B) is a graph showing the vertical displacement of the axle when passing over a bridge, (C) is a graph showing the application result after filter processing and envelope processing of the vertical displacement of the axle when passing over a bridge after filter processing and envelope processing, and (D) is a graph showing the application result after differential processing of the vertical displacement of the axles of the leading and trailing vehicles after envelope processing. FIG. 13 is an overall view illustrating a bridge resonance detection system according to a fourth embodiment of the present invention. FIG. 13 is an overall view illustrating a bridge resonance detection system according to a fifth embodiment of the present invention. FIG. 13 is a schematic diagram illustrating a bridge resonance detection system according to a fifth embodiment of the present invention.

First Embodiment
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
The track R shown in Fig. 1 and Fig. 2 is a passage (railway) on which the train T runs. The track R includes a pair of left and right rails that guide the wheels of the train T. As shown in Fig. 9, the track R is, for example, a double track made up of two main lines, and includes an up line on which the train T runs from the end point to the start point, and a down line on which the train T runs from the start point to the end point.

A train T shown in Figs. 1, 2 and 9 is a moving body moving along a track R. The train T is a railway vehicle such as an electric car, a diesel car or a passenger car running on a bridge B. The train T shown in Figs. 1 and 2 is, for example, a Shinkansen (registered trademark) railway vehicle running at high speed. The train T is a commercial train organized for the purpose of transporting passengers or freight. For example, as shown in Fig. 1, the train T is made up of 12 commercial cars with a car length (car body length) L _C of about 25 m. When the train T runs on a bridge B, the wheels of the train T periodically apply a load to the bridge B due to the regular axle arrangement, causing the bridge B to vibrate.

As shown in Figs. 1, 2 and 9, the train T is made up of cars _VF , _VM and _VL , and moves across the bridge B at a substantially constant speed. Car _VF is the leading car located at the front of the train, car _VM is the middle car located in the middle of the train, and car _VL is the rear car (last car) located at the rear of the train. As shown in Figs. 1 and 2, the cars _VF , _VM and _VL are equipped with bogies _T1 and _T2 , and one car body is supported by the two bogies _T1 and _T2 . The bogies _T1 and _T2 are devices that support the car bodies of the cars _VF , _VM and _VL and run on the track R. The bogies _T1 and T2 shown in Figs. 1 and ₂ are two-axle bogies (bogies) made up of two pairs of axles, and support one end and the other end of the car body of each of the cars _VF , _VM and _VL . Bogie _T1 is a first bogie arranged at the front of each vehicle _VF , _VM , _VL in the direction of travel and supporting one end of the vehicle body, and bogie _T2 is a second bogie arranged at the rear of each vehicle _VF , _VM , _VL in the direction of travel and supporting the other end of the vehicle body.

The bridge B shown in Fig. 1 and Fig. 9 is a fixed structure constructed to form a space below the track R. The bridge B is constructed to cross a water area such as a river, a valley, or a lake, or a transportation route such as a road or a railway. The bridge B is, for example, a concrete railway bridge of a type of reinforced concrete structure (RC structure) in which concrete is the main material, or a prestressed concrete structure (PRC structure) in which cracks are permitted to occur under normal use conditions and the crack width is controlled by arranging deformed steel bars and introducing prestressing. As shown in Fig. 1, the bridge B includes a beam _B1 , a column _B2 , a short-span bridge _B3 , and the like. The bridge B is, for example, a rigid-frame viaduct of a rigid-frame structure in which the beam _B1 and the column _B2 are constructed individually. The beam _B1 is a structure arranged horizontally to support the track R. The column _B2 is a structure supporting the beam _B1 . The columns _B2 are constructed at a predetermined interval along the length of the bridge B, and are reinforced concrete columns arranged vertically. The short-span bridge _B3 is a structure placed between the beams _B1 of the bridge B. As shown in FIG. 1, the short-span bridge _B3 is a bridge in which the span length Lb of the short-span bridge _B3 is shorter than the vehicle length _Lc of the cars _VF , _VM , and _VL of the train _T. The short-span bridge _B3 is, for example, an adjustable girder such as a Gerber girder with a hinge inserted into a continuous bridge such as a rigid frame viaduct. The short-span bridge _B3 is, for example, a bridge with a span length _Lb of about 10 m.

The resonance detection system 1 shown in Figures 2 and 3 is a system that detects resonance of a short-span bridge _B3 over which a train T runs. As shown in Figure 3, the resonance detection system 1 includes an acceleration measuring device 2, a communication device 3, and a resonance detection device 4. The resonance detection system 1 transmits the measurement results of the acceleration measuring device 2 to the resonance detection device 4 via the communication device 3, and detects resonance of the short-span bridge _B3 based on the measurement results of the acceleration measuring device 2.

The acceleration measuring device 2 shown in Figs. 2 to 4 is a device that measures the measurement data _D1 required for detecting a resonant bridge from the train T side. The acceleration measuring device 2 measures the vertical acceleration of the train T from the train T side as the measurement data (vehicle measurement data) _D1 required for detecting a resonant bridge. The acceleration measuring device 2 measures the vertical acceleration of the leading vehicle _VF and the trailing vehicle _VL . The acceleration measuring device 2 measures vibrations that occur in the train T when the train T moves, and measures the vertical acceleration of the body of the vehicle VF of the train _T and the vertical acceleration of the body of the vehicle _VL of the train T. The acceleration measuring device 2 measures the vertical acceleration of the vehicles _VF and _VL while moving together with the train T. As shown in Fig. 4, the acceleration measuring device 2 includes acceleration detecting units 2a and 2b, a speed detecting unit 2c, a position detecting unit 2d, a measurement data storage unit 2e, a measurement data transmitting unit 2f, a control unit 2g, and the like.

The acceleration detection units 2a and 2b shown in Fig. 2 and Fig. 4 are means for detecting the vertical acceleration of the train T. The acceleration detection unit 2a detects the vertical acceleration (vertical vibration acceleration) of the car _VF of the train T, and the acceleration detection unit 2b detects the vertical acceleration (vertical vibration acceleration) of the car _VL of the train T. The acceleration detection units 2a and 2b are both of the same structure, and are accelerometers that detect the vertical acceleration (on-board acceleration) of the leading car _VF and the trailing car _VL . The acceleration detection units 2a and 2b can use, for example, a car body vibration acceleration sensor for train vibration management that is mounted on many high-speed railway cars. For example, as shown in Fig. 2, the acceleration detection units 2a and 2b detect the vibration of the cars _VF and _VL at detection positions P _F and P _L equidistant L ₀ from the center part O of the train T. The acceleration detection units 2a and 2b detect the vertical acceleration above the bogie _T1 of the leading car _VL and above the bogie _T2 of the trailing car _VL . The acceleration detection unit 2a is installed, for example, on the car body floor directly above the _bogie (first bogie) _T1 on the front side in the traveling direction of the leading vehicle VL, and the acceleration detection unit 2b is installed on the car body floor directly above the _bogie (second bogie) _T2 on the rear side in the traveling direction of the trailing vehicle VL. As shown in Fig. 4, the acceleration detection unit 2a outputs the detected vertical acceleration to the control unit 2g as leading vehicle acceleration data _D11 , and the acceleration detection unit 2b outputs the detected vertical acceleration to the control unit 2g as trailing vehicle acceleration data _D12 .

The speed detection unit 2c is a means for detecting the traveling speed of the train T. The speed detection unit 2c is a speedometer such as a tachograph that detects the rotation of the wheels of the train T and generates a pulse signal according to the number of rotations of the wheels. For example, the speed detection unit 2c generates a predetermined number of pulse signals (distance pulse signals) for each rotation of the wheels of the train T to detect the number of rotations of the wheels, and outputs the detection result to the control unit 2g as train speed data (moving object speed data) _D13 .

The position detection unit 2d is a means for detecting the position of the train T. The position detection unit 2d includes, for example, an ATS on-board device installed on the train T side for mutually transmitting and receiving information with an ATS ground device of an automatic train stop device (ATS (Automatic Train Stop)) installed at a specific point on the track R side, an ATS receiver that receives a signal from the ATS on-board device and outputs absolute position data representing the distance from the starting point (departure point) to the ATS ground device, and a calculation unit that detects the absolute position of the train T based on the absolute position data output by the ATS receiver and calculates the current position of the train T by integrating the pulse signals output by the speed detection unit 2c until the train T arrives at the next ATS ground device. The position detection unit 2d calculates the moving distance (travel distance) of the train T from the starting point based on the train speed data _D13 output by the speed detection unit 2c and the absolute position data output by the ATS receiver, and outputs the current position of the train T to the control unit 2g as train position data (mobile body position data) _D14 .

The measured data storage unit 2e is a means for storing various data related to the acceleration measuring device 2. The measured data storage unit 2e is, for example, a storage device that stores the measurement results of the acceleration measuring device 2 as measured data _D1 . As shown in Fig. 5, the measured data storage unit 2e stores the leading vehicle acceleration data _D11 output by the acceleration detection unit 2a, the trailing vehicle acceleration data _D12 output by the acceleration detection unit 2b, the train speed data _D13 output by the speed detection unit 2c, the train position data _D14 output by the position detection unit 2d, and the measurement date data _D15 on which the acceleration measuring device 2 measured each data as measured data _D1 . The measured data storage unit 2e stores the leading vehicle acceleration data _D11 and the trailing vehicle acceleration data D12 in chronological order according to the measurement date data _D15 , in correspondence with the train speed data _D13 output by the speed detection unit 2c and the train position data _D14 output by the position detection unit _2d , every time the train T passes the short span bridge _B3 .

The measurement data transmission unit 2f shown in Fig. 4 is a means for transmitting the measurement data D _1. The measurement data transmission unit 2f is a transmitter or the like that transmits the measurement data D ₁ stored in the measurement data storage unit 2e from the train T to the resonance detection device 4.

The control unit 2 g is a central processing unit (CPU) that controls various operations related to the acceleration measuring device 2 . The control unit 2g, for example, outputs the leading vehicle acceleration data _D11 output by the acceleration detection unit 2a to the measured data storage unit 2e, commands the measured data storage unit 2e to store the leading vehicle acceleration data _D11 , outputs the tail vehicle acceleration data _D12 output by the acceleration detection unit 2b to the measured data storage unit 2e, commands the measured data storage unit 2e to store the tail vehicle acceleration data _D12 , outputs the train speed data _D13 output by the speed detection unit 2c to the measured data storage unit 2e, commands the measured data storage unit 2e to store the train speed data _D13 , outputs the train position data _D14 output by the position detection unit 2d to the measured data storage unit 2e, commands the measured data storage unit 2e to store the train position data _D14 , reads out the measured data _D1 from the measured data storage unit 2e and outputs it to the measured data transmission unit 2f, and commands the measured data transmission unit 2f to transmit the measured data _D1 . The control unit 2g is connected to be able to communicate with the acceleration detection units 2a and 2b, the speed detection unit 2c, the position detection unit 2d, the measurement data storage unit 2e, and the measurement data transmission unit 2f.

3 and 4 is a device that transmits measurement data _D1 from the acceleration measuring device 2 to the resonance detecting device 4. The communication device 3 is an electric communication line such as a telephone line or an internet line that connects the measurement data transmitting unit 2f of the acceleration measuring device 2 to the measurement data receiving unit 4a of the resonance detecting device 4 so that they can communicate with each other in order to transmit the measurement data _D1 from the measurement data transmitting unit 2f of the acceleration measuring device 2 to the measurement data receiving unit 4a of the resonance detecting device 4.

The resonance detection device 4 shown in Fig. 2 to Fig. 4 is a device that detects resonance of the short-span bridge _B3 on which the train T runs. The resonance detection device 4 detects the short-span bridge _B3 that is experiencing N-th order resonance (N is an integer of 2 or more) based on the measurement data D1 of the train T side measured from the train T side. The resonance detection device 4 removes components other than the components at ₁ /N (N is an integer of 2 or more) of the vehicle length that are caused by the resonating bridge from the measurement data _D1 measured by the acceleration measurement device 2, and extracts vibration components specific to the resonating bridge. The resonance detection device 4 detects the resonance of the short-span bridge _B3 from the difference between the amplitude of the vibration component specific to the resonating bridge measured by the leading vehicle _VF and the amplitude of the vibration component specific to the resonating bridge measured by the trailing vehicle _VL . As shown in Fig. 3, the resonance detection device 4 includes a measurement data receiving unit 4a, a measurement data storage unit 4b, a vibration component extracting unit 4c, a vibration amplitude estimating unit 4d, a difference calculating unit 4e, a resonance detecting unit 4f, a detection result data storage unit 4g, a resonance detection program storage unit 4h, a display unit 4i, and a control unit 4j. The resonance detection device 4 is configured, for example, with a personal computer, and causes the computer to execute a predetermined process according to the resonance detection program. The resonance detection device 4 executes the resonance detection program on a track maintenance management database system (Laboratory's Conversational System (LABOCS)) that analyzes and processes railway-related data, such as track displacement and vehicle vibration, from various angles.

Next, the resonance phenomenon of a railway bridge when a train passes will be explained.
The following explanation uses a short-span bridge with third-order resonance as an example. Also, explanations are given using the results of a mutual simulation of a railway bridge modeled as a two-dimensional simple beam and a vehicle modeled as a two-dimensional multibody. The specifications of the railway bridge and vehicle are assumed to be typical of Japanese railway bridges and high-speed vehicles, with a span length of 50 m, natural frequency of 2.8 Hz, modal damping ratio of 2%, unit length mass of 25 t/m, vehicle length of 25 m, bogie center distance of 17.5 m, axle distance within the bogie of 2.5 m, axle load of 120 kN, and number of cars in the train.

Figure 6 is a graph showing the deflection waveforms at the center of the span of a short-span bridge when a vehicle passes at several train speeds of 200, 230, 250, 270, and 300 km/h. The vertical axis in Figure 6 is vertical displacement [m], and the horizontal axis is dimensionless time, with the time it takes for one vehicle (25 m long) to pass being 1. As shown in Figure 6, the characteristics of the dynamic response amplification seen in the deflection waveform at the center of the span of a short-span bridge change significantly depending on the train speed, and it is maximum at 250 km/h as shown in Figure 6 (C). This dynamic response amplification occurs when the natural frequency of the third-order deflection mode of the short-span bridge and the excitation frequency of the running train approach each other and resonate. The excitation period of the running train is due to the regular axle arrangement of the vehicles, but for short-span bridges that are shorter than the vehicle length and have a span length shorter than 30 m, the main excitation component is an interval of 1/3 of the vehicle length of 25 m. Therefore, if the train speed is v [m/s], the vehicle length is _Lc [m], and the natural frequency of the short-span bridge is n [Hz], the condition for resonance to occur is v/ _Lc /3 = n, and the train speed v = _vres that satisfies this is called the resonant speed and is expressed by the following equation 1.

In Fig. 6(C), 2.8[Hz] x 25[m] = 70[m/s] is about 250km/h, and the dynamic response amplification is maximum, which roughly corresponds to the condition of equation 1. The state shown in Fig. 6(C) is a resonant state, and a bridge in this state is a resonant bridge. The states shown in Figs. 6(A), (B), (D), and (E) are non-resonant states, where the train's running speed is far from the resonant speed, and there is almost no dynamic response amplification when a train passes. The resonance detection device 4 detects a bridge in a _resonant state or close to resonant state where the dynamic response increases sharply as shown in Fig. 6(C) as a resonant bridge, based on on-board measurement data such as measurement data D1.

In order to understand the characteristics of the dynamic response observed on a vehicle when traveling on a resonant bridge, a simple theoretical analysis is performed. Figure 7 shows a simply supported beam model under the action of a moving load for theoretical analysis. Here, _Lc shown in Figure 7 is the vehicle length, P is the moving concentrated load (moving load) per vehicle length, _vres is the resonance speed (train speed at resonance), _Lb is the span length (girder span (span length)) which is the distance between the supports of the short-span bridge _B3 , _zb (x, t) is the girder displacement (vertical displacement) at position x and time t of the simply supported beam with span length _Lb , and _Ares is the dynamic response amplitude of the beam at resonance (dynamic amplitude at resonance). x is the position in the bridge axis direction with the left end of the girder of the short-span bridge _B3 being zero, and t is the time when the time when the leading moving concentrated load P enters the girder is zero. It is assumed that the number of moving concentrated loads P is sufficiently large and the short-span bridge _B3 is in a steady state. In this case, the dynamic response component z _b,d (x _p ) of the beam at a position x _p on the beam where a moving concentrated load P passing through the beam in a resonant state acts is expressed by the following equation 2.

Equation 2 means that the dynamic response component z _b,d (x _p ) of the resonating bridge when viewed from the position x _p of the moving concentrated load P is a combination of a wave with a wavelength equal to the vehicle length L _c (vehicle length component) and a wave with a wavelength equal to 2L _b , which is twice the bridge span length (span length component).

FIG. 8 shows an example of the dynamic response component z b,d (x p ) at the position x _p of the moving concentrated load P of the resonating bridge calculated by _Equation 2, assuming that the span length is 10 m, the _{vehicle length} is 25 _m , and the dynamic response amplitude A res of the beam at resonance is 1. The vertical axis in FIG. 8 represents the dynamic response amplitude, and the horizontal axis represents the distance [m] from the girder end (left end of the bridge). The theoretical waveform shown in FIG. 8 exhibits the characteristic that the maximum amplitude of the wave corresponding to 1/3 of the vehicle length L _c increases and decreases in accordance with the half sine wave (span length component) corresponding to the span length L _b . By utilizing this characteristic, it is possible to more accurately separate other vibration components mixed into the measurement of vertical acceleration from the vibration components originating from the resonating bridge.

Next, the detection principle of the bridge resonance detection device according to the first embodiment of the present invention will be described.
In the following, an example will be described in which the resonance detection device 4 detects a short-span bridge _B3 that resonates in a third order.
The resonance detection device 4 shown in Fig. 2 and Fig. 3 detects a resonant bridge based on the presence or absence of a component of 1/3 of the vehicle length L _C mixed in the vehicle body vertical acceleration of the rear vehicle V _L of the train T passing over the resonant bridge. As shown in Fig. 9, the resonance detection device 4 performs signal processing ( _filter and envelope processing) to emphasize the vibration component specific to the resonant bridge based on the vehicle body vertical acceleration measured by the front vehicle V F and the rear vehicle V _L of the train T, and performs differential processing of the front vehicle V _F and the rear vehicle V _L to cancel the influence of other vibration components and extract only the vibration component (component of 1/3 of the vehicle length L _C ) caused by the resonant bridge. The resonance detection device 4 uses the difference value (envelope difference) of the envelope-processed waveform as a detection index, and judges that the short-span bridge B ₃ is a resonant bridge when this detection index forms a dominant component corresponding to the span length L _b of the short-span bridge B ₃ over which the train T passes.

(Filtering)
The resonance detection device 4 performs filtering to reduce components other than 1/3 of the vehicle length L _C caused by the resonating bridge from among various components mixed in the vertical acceleration of the vehicle body. The resonance detection device 4 extracts the 1/3 of the vehicle length L _C component mixed in the response of the rear vehicle V _L when passing through the resonating bridge. The resonance detection device 4 identifies a wavelength component (1/3 of the vehicle length L _C ) specific to the short-span bridge B 3 that resonates third order. Since the natural vibration of the short-span bridge B ₃ is excited in three waves during the passing time of one vehicle (25 m), the resonance detection device 4 detects the short-span bridge B ₃ that resonates third order by performing band-pass filter (BPF) processing with a pass band around a wavelength of 25/3 = _8.33 m, which corresponds to the waveform of the dynamic response component z b, _d (x _p ) shown in Figure 8.

(Envelope Processing)
The resonance detection device 4 performs envelope processing on the vehicle body vertical acceleration waveform after filtering to realize a difference processing robust against position synchronization errors of the leading vehicle _VF and the trailing vehicle _VL and measurement errors of the acceleration sensors. As shown in FIG. 8, the resonance detection device 4 performs envelope processing to estimate the amplitude of a waveform corresponding to a span length component from the waveform of the dynamic response component z _b,d (x _p ) extracted by filtering. The resonance detection device 4 uses the envelope processing to significantly reduce random errors such as observation noise that increase with the difference processing. For example, the resonance detection device 4 detects a peak position using a differential value of the filtered waveform, and estimates an envelope by connecting the maximum or minimum value of this peak value. The resonance detection device 4 lengthens the period of the waveform used in the difference processing by the envelope processing to reduce the influence of position synchronization errors of the leading vehicle _VF and the trailing vehicle _VL . Assuming that the vehicle vibration acceleration sensors of the leading vehicle _VF and the trailing vehicle _VL are of the same type and that the mixed-in measurement noise is generated in the same way, the resonance detection device 4 converts the evaluation as a waveform into an evaluation as an amplitude amount by envelope processing, thereby canceling out the measurement noise when differential processing is performed, thereby significantly reducing the measurement noise.

(Differential processing of leading and trailing vehicles)
As shown in Fig. 8, the resonance detection device 4 converts the component of 1/3 of the vehicle length Lc of the resonating bridge included in the vehicle body vertical acceleration into a dominant component of a half-sine wave shape corresponding to the span length _Lb of the short-span bridge _B3 by filter processing and envelope _processing . If track displacement with a wavelength close to 1/3 of the vehicle length _Lc or quasi-static deformation of the bridge exists in addition to the displacement of the resonating bridge, these effects are also included. Therefore, even if a dominant component corresponding to the span length _Lb exists in the waveform after filter processing and envelope processing, it is not possible to determine whether it is due to the resonance of the short-span bridge _B3 or due to other factors. As shown in Fig. 9, the resonance detection device ₄ performs filter processing and envelope processing on the two vehicle body vertical accelerations measured by the leading vehicle _VF and the trailing vehicle _VL , and then cancels vibration components other than resonance by differential processing in which the leading vehicle _VF is subtracted from the trailing vehicle VL. Since the dynamic response amplitude of the bridge during resonance is amplified as the train T passes, the component of 1/3 of the vehicle length _Lc caused by resonance that predominates when the rear vehicle _VL passes is hardly generated when the leading vehicle _VF passes. On the other hand, the quasi-static deformation of the bridge, the track configuration, the track distortion, the track irregularities such as rail unevenness, etc. do not change when the leading vehicle _VF and the trailing vehicle _VL pass, so the car body vertical acceleration caused by these components is also approximately equal for the leading vehicle _VF and the trailing vehicle _VL . The resonance detection device 4 extracts only the predominant component corresponding to the span length _Lb of the short-span bridge _B3 that is generated due to the resonating bridge by differential processing.

The measurement data receiving unit 4a shown in Fig. 3 is a means for receiving the measurement data _D1 transmitted by the acceleration measuring device 2. The measurement data receiving unit 4a receives the measurement data _D1 transmitted by the acceleration measuring device 2 through the communication device 3. The measurement data storage unit 4b is a means for storing the measurement data _D1 transmitted by the acceleration measuring device 2. The measurement data storage unit 4b is, for example, a storage device that stores the measurement data _D1 transmitted by the acceleration measuring device 2 in chronological order as shown in Fig. 5.

The vibration component extracting unit 4c shown in Fig. 3 is a means for extracting vibration components specific to a resonant bridge based on the measurement results of the acceleration measuring device 2. Here, the vibration components specific to a resonant bridge are vibrations whose main component is 1/3 of the vehicle length _Lc . The vibration component extracting unit 4c extracts the vibration whose main component is 1/3 of the vehicle length _Lc as the vibration components specific to a resonant bridge. The vibration component extracting unit 4c extracts the vibration components specific to a resonant bridge from the leading vehicle acceleration data _D11 and the trailing vehicle acceleration data _D12 stored in the measurement data storage unit 4b. The vibration component extracting unit 4c extracts the vibration components specific to the resonant bridge of the leading vehicle _VF from the measurement results (vertical acceleration waveform) of the acceleration measuring device 2, and extracts the vibration components specific to the resonant bridge of the trailing vehicle _VL from the measurement results (vertical acceleration waveform) of the acceleration measuring device 2. The vibration component extraction unit 4c passes only the vibration (vehicle length irregularity) whose main component is _1/3 of the vehicle length Lc from the measured waveform showing the time change of the vertical acceleration including the displacement (bridge response) of the short-span bridge _B3 , and removes the vibration other than the vibration whose main component is 1/3 of the vehicle length _Lc . The vibration component extraction unit 4c is, for example, a band-pass filter that passes a specific frequency component, and functions as a filter unit such as a digital filter. The vibration component extraction unit 4c extracts _the vibration component sin(6πx/ _Lc + _θres ) specific to the resonant bridge by band-pass filter processing from the waveform of the dynamic response component _zb,d ( _xp ) of the short-span bridge B3 shown in FIG. 8. The vibration component extraction unit 4c outputs the extracted vibration component specific to the resonant bridge to the vibration amplitude estimation unit 4d as vibration component data.

The vibration amplitude estimation unit 4d shown in Fig. 3 is a means for estimating the amplitude of the vibration component specific to the resonating bridge measured by the leading vehicle _VF and the trailing vehicle _VL . The vibration amplitude estimation unit 4d estimates the amplitude of the vibration component specific to the resonating bridge of the leading vehicle _VF based on the measurement result of the acceleration measurement device 2, and estimates the amplitude of the vibration component specific to the resonating bridge of the trailing vehicle _VL based on the measurement result of the acceleration measurement device 2. The vibration amplitude estimation unit 4d estimates the amplitude of the vibration whose main component is 1/3 of the vehicle length _Lc by envelope processing. The vibration amplitude estimation unit 4d performs envelope processing on the waveform of the dynamic response component zb _,d ( _xp ) of the short-span bridge _B3 shown in Fig. 8, whose wavelength is 1/3 of the vehicle length _Lc , generates an envelope sin(2πx/ _2Lb ) whose wavelength is _2Lb, which is twice the span length _Lb , and estimates the amplitude of this envelope sin(2πx/ _2Lb ). Here, the envelope processing is a process for estimating the envelope sin(2πx/2L _b ) of the waveform of the dynamic response component z _b,d (x _p ) of the short-span bridge _B3 shown in Fig. 8. The vibration amplitude estimation unit 4d outputs the estimated amplitude of the vibration component specific to the resonating bridge to the difference calculation unit 4e as vibration amplitude data.

The difference calculation unit 4e shown in Fig. 3 is a means for calculating the difference in amplitude of the vibration component specific to the resonant bridge measured by the leading vehicle _VF and the trailing vehicle _VL . The difference calculation unit 4e calculates the difference in amplitude of the vibration component specific to the resonant bridge that predominates only in the trailing vehicle _VL by subtracting the amplitude of the vibration component specific to the resonant bridge of the leading vehicle _VF from the amplitude of the vibration component specific to the resonant bridge of the trailing vehicle _VL . The difference calculation unit 4e calculates the difference in vertical acceleration including bridge displacement of the leading vehicle _VF and the trailing vehicle _VL after bandpass filter processing and envelope processing. The difference calculation unit 4e outputs the calculated difference in amplitude of the vibration component specific to the resonant bridge to the resonance detection unit 4f as difference data.

The resonance detection unit 4f is a means for detecting resonance of the short-span bridge _B3 based on vibration components specific to a resonant bridge. The resonance detection unit 4f detects the short-span bridge _B3 based on the measurement results of the acceleration measurement device 2. The resonance detection unit 4f detects resonance of the short-span bridge B3 based on the measurement results of the acceleration measurement device 2 that measures the vertical acceleration of the leading vehicle _VF and the measurement results of the acceleration measurement device 2 that measures the vertical acceleration of the trailing vehicle _VL . The resonance detection unit 4f detects resonance of the short-span bridge _B3 based on the difference between the vibration components specific to _the resonant bridge measured by the leading vehicle _VF and the trailing vehicle VL. The resonance detection unit 4f calculates the difference (envelope _difference ) between the vibration components specific to the resonant bridge measured by the leading vehicle _VF and the trailing vehicle _VL as a resonant bridge detection index RDI, which is an index for detecting whether the short-span bridge _B3 is resonating or not. The resonance detection unit 4f evaluates whether or not the short-span bridge _B3 of any span length _Lb , which the train T has passed through, is resonating based on the resonant bridge detection index RDI. For example, when the resonant bridge detection index RDI exceeds a predetermined value (threshold), the resonance detection unit 4f evaluates that the short-span bridge _B3 is in a resonant state or close to resonating, and when the resonant bridge detection index RDI is equal to or less than the predetermined value (threshold), the resonance detection unit 4f evaluates that the short-span bridge _B3 is not in a resonant state. The resonance detection unit 4f outputs the detection result of whether or not the short-span bridge _B3 is resonating to the control unit 4j as detection result data.

The detection result data storage unit 4g is a means for storing the detection results of the resonance detection unit 4f. The detection result data storage unit 4g is, for example, a storage device that stores the detection result data output by the resonance detection unit 4f in chronological order for each short-span bridge _B3 .

The resonance detection program storage unit 4h is a means for storing a resonance detection program for detecting resonance of the short-span bridge _B3 over which the train T runs. The resonance detection program storage unit 4h is a storage device or the like that stores a resonance detection program read from an information recording medium or a resonance detection program downloaded through an electric communication line.

The display unit 4i is a means for displaying various information related to the resonance detection device 4. The display unit 4i is a display device that displays, for example, the measurement results of the acceleration measurement device 2 and the detection results of the resonance detection unit 4f on a screen. The display unit 4i displays, for example, the leading vehicle acceleration data _D11 and the trailing vehicle acceleration data _D12 on a screen in correspondence with the train position data _D14 as shown in Fig. 5, and also displays the presence or absence of resonance for each short-span bridge _B3 through which the train T passes in correspondence with the train position data _D14 .

The control unit 4j is a central processing unit (CPU) that controls various operations related to the resonance detection device 4. The control unit 4j reads out a resonance detection program from the resonance detection program storage unit 4h, and executes a resonance detection process in accordance with the resonance detection program. The control unit 4j, for example, reads out the leading vehicle acceleration data _D11 and the trailing vehicle acceleration data _D12 from the measurement data storage unit 4b and outputs them to the vibration component extraction unit 4c, instructs the vibration component extraction unit 4c to extract the vibration component specific to the resonating bridge from the leading vehicle acceleration data _D11 and the trailing vehicle acceleration data _D12 , instructs the vibration amplitude estimation unit 4d to estimate the amplitude of the vibration component specific to the resonating bridge, instructs the difference calculation unit 4e to calculate the difference between the amplitudes of the vibration component specific to the resonating bridge measured by the leading vehicle _VF and the trailing vehicle _VL , instructs the resonance detection unit 4f to detect whether the short-span bridge _B3 is resonating or not, outputs the detection result data output by the resonance detection unit 4f to the detection result data storage unit 4g, instructs the detection result data storage unit 4g to store the detection result data, and instructs the display unit 4i to display various data. The control unit 4j is communicatively connected to the measurement data receiving unit 4a, the measurement data memory unit 4b, the vibration component extraction unit 4c, the vibration amplitude estimation unit 4d, the difference calculation unit 4e, the resonance detection unit 4f, the detection result data memory unit 4g, the resonance detection program memory unit 4h, and the display unit 4i.

Next, a method for detecting resonance of a bridge according to a first embodiment of the present invention will be described.
FIG. 10 is a graph showing an example of the case where the resonance detection method is applied to the displacement components of a short-span bridge _B3 with a span length of 10 m measured by the leading vehicle _VF and the trailing vehicle _VL . FIG. 10(A) is a graph showing the vertical displacement at the center of the bridge span when a train passes through at train speeds of 200, 230, 250, 270, and 300 km/h. The vertical axis shown in FIG. 10(A) is vertical displacement [m], and the horizontal axis is time [s]. FIG. 10(B) is a graph showing the vehicle body vertical acceleration directly above the first bogie of the leading vehicle _VF and the second bogie of the trailing vehicle _VL when passing through the bridge. The vertical axis shown in FIG. 10(B) is vertical acceleration [m/ ^s2 ]. FIG. 10(C) is a graph showing the application result after band pass filter (BPF) processing and envelope processing to the vehicle body vertical acceleration when passing through the bridge. The vertical axis shown in Figure 10(C) is the vertical acceleration [m/ ^s2 ]. Figure 10(D) is a graph showing the application result after differential processing of the envelope-processed vehicle vertical acceleration of the leading vehicle _VF and the trailing vehicle _VL . The vertical axis shown in Figure 10(D) is the envelope difference [m/ ^s2 ]. The horizontal axis shown in Figures 10(B) to (D) is the position [m] from the left end of the bridge.

The resonance detection method #100 shown in Fig. 11 is a method for detecting resonance of the short-span bridge _B3 on which the train T runs. The resonance detection method #100 includes a vibration component extraction step #110, a vibration amplitude estimation step #120, a difference calculation step #130, and a resonance detection step #140. In the resonance detection method #100, components other than the component of 1/3 of the vehicle length _Lc are removed from the measurement data _D1 measured by the acceleration measurement device 2 shown in Figs. 2 to ₄ , and a vibration component specific to the resonating bridge is extracted. In the resonance detection method #100, the resonance of the short-span bridge B3 is detected from the difference between the amplitude of the vibration component specific to the resonating bridge measured by the leading vehicle VF and the amplitude of the vibration component specific to the resonating _bridge measured by the trailing vehicle _VL .

The vibration component extraction process #110 is a process of extracting vibration components specific to a resonating bridge based on the measurement results of the acceleration measuring device 2. In the vibration component extraction process #110, a vibration having 1/3 of the vehicle length _Lc as a main component is extracted as a vibration component specific to a resonating bridge. In the vibration component extraction process #110, as shown in FIG. 10(B), from the vertical acceleration measured by the acceleration measuring device 2 on the body of the leading vehicle _VF and the vertical acceleration measured by the acceleration measuring device 2 on the body of the trailing vehicle _VL , displacement components other than the displacement component of the short-span bridge _B3 are removed by filtering (BPF processing) as shown in FIG. 10(C). As a result, the vertical acceleration of only the bridge displacement measured by the bogie _T2 of the leading vehicle _VF and the vertical acceleration of only the bridge displacement measured by the bogie _T1 of the trailing vehicle _VL are extracted as vibration components specific to a resonating bridge having 1/3 of the vehicle length _Lc as a main component.

The vibration amplitude estimation process #120 is a means for estimating the amplitude of the vibration component specific to the resonant bridge measured by the leading vehicle _VF and the trailing vehicle _VL . In the vibration amplitude estimation process #120, the amplitude of the vibration component specific to the resonant bridge of the leading vehicle _VF is estimated based on the measurement result of the acceleration measurement device 2, and the amplitude of the vibration component specific to the resonant bridge of the trailing vehicle _VL is estimated based on the measurement result of the acceleration measurement device 2. In the vibration amplitude estimation process #120, the vibration component specific to the resonant bridge of the leading vehicle VF shown in _FIG . 10(C) and the vibration component specific to the resonant bridge of the trailing vehicle _VL are envelope-processed. As a result, the amplitude of the vibration component specific to the resonant bridge of the leading vehicle _VF and the amplitude of the vibration component specific to the resonant bridge of the trailing vehicle _VL are estimated.

The difference calculation step #130 is a step of calculating the difference in amplitude of the vibration component specific to the resonating bridge measured by the leading vehicle _VF and the trailing vehicle _VL . In the difference calculation step #130, as shown in Fig. 10(D), the amplitude of the vibration component specific to the resonating bridge of the leading vehicle _VF is subtracted from the amplitude of the vibration component specific to the resonating bridge of the trailing vehicle _VL to calculate the resonating bridge detection index RDI corresponding to the envelope difference.

The resonance detection process #140 is a process of detecting resonance of the short-span bridge _B3 based on vibration components specific to the resonating bridge. In the resonance detection process #140, the short-span bridge _B3 is detected based on the measurement results of the acceleration measurement device 2. In the resonance detection process #140, the resonance of the short-span bridge _B3 is detected based on the measurement results of the acceleration measurement device 2 that measures the vertical acceleration of the leading vehicle _VF and the measurement results of the acceleration measurement device 2 that measures the vertical acceleration of the trailing vehicle _VL . In the resonance detection process #140, the resonance of the short-span bridge _B3 is detected based on the difference in amplitude of the vibration components specific to the resonating bridge of the leading vehicle _VF and the trailing vehicle _VL . In the resonance detection process #140, when the resonating bridge detection index RDI shown in FIG. 10(D) exceeds a predetermined value, it is determined that the short-span bridge _B3 is resonating, and when the resonating bridge detection index RDI is equal to or less than the predetermined value, it is determined that the short-span bridge _B3 is not resonating. For example, as shown in Fig. 10(D), when the train speed is 250 km/h, the resonant bridge detection index RDI is relatively large, and the short-span bridge _B3 is detected as resonating. On the other hand, as shown in Fig. 10(D), when the train speed is 200 and 300 km/h, the resonant bridge detection index RDI is relatively small, and the short-span bridge _B3 is detected as not resonating. Also, as shown in Fig. 10(D), when the train speed is 230 km/h, the resonant bridge detection index RDI is smaller than when resonating but larger than when not resonating, and the short-span bridge _B3 is detected as close to resonating.

Next, the operation of the bridge resonance detection device according to the first embodiment of the present invention will be described.
The following description will focus on the operation of the control unit 4j.
12, the control unit 4j reads the resonance detection program from the resonance detection program storage unit 4h. When the control unit 4j reads the resonance detection program, the control unit 4j starts a series of resonance detection processes.

In S200, the control unit 4j commands the vibration component extraction unit 4c to extract vibration components specific to a resonant bridge. The control unit 4j reads out the leading vehicle acceleration data _D11 measured by the leading vehicle _VF measured by the acceleration measurement device 2 and the trailing vehicle acceleration data _D12 measured by the trailing vehicle _VL measured by the acceleration measurement device 2 from the measurement data storage unit 4b, and outputs the leading vehicle acceleration data _D11 and the trailing vehicle acceleration data _D12 to the vibration component extraction unit 4c. For this reason, the vibration component extraction unit 4c extracts the vibration components specific to a resonant bridge, whose main component is 1/3 of the vehicle length _Lc , by bandpass filter processing from the waveform of the dynamic response component zb _,d ( _xp ) of the short-span bridge _B3 shown in Figure 8. As a result, as shown in FIG. 10(C), the vibration component extraction unit 4c extracts vibration components specific to the resonating bridge of the leading vehicle _VF and the trailing vehicle _VL , and outputs the vibration component data to the vibration amplitude estimation unit 4d.

In S300, the control unit 4j commands the vibration amplitude estimation unit 4d to estimate the amplitude of the vibration component specific to the resonating bridge. As a result, the vibration amplitude estimation unit _4d estimates the amplitude of the vibration component specific to the resonating bridge measured by the leading vehicle VF and the amplitude of the vibration component specific to the resonating bridge measured by the trailing vehicle _VL based on the measurement results of the acceleration measurement device 2. The vibration amplitude estimation unit 4d performs envelope processing on the waveform of the dynamic response component z _b,d (x _p ) of the short-span bridge _B3 , _whose wavelength is 1/3 of the vehicle length L _c shown in Figure 8, and generates an envelope sin(πx/L _b ) whose wavelength is 2L _{b, twice the span length L b} . As a result, as shown in FIG. 10(C), the vibration amplitude estimation unit 4d performs envelope processing on the amplitudes of the vibration components specific to the resonating bridge of the leading vehicle _VF and the trailing vehicle _VL , estimates the amplitude of this envelope sin(πx/ _Lb ), and outputs it to the difference calculation unit 4e as vibration amplitude data.

In S400, the control unit 4j commands the difference calculation unit 4e to calculate the difference in the amplitude of the vibration component specific to the resonant bridge measured by the leading vehicle _VF and the trailing vehicle _VL . Therefore, the difference calculation unit 4e subtracts the amplitude of the vibration component specific to the resonant bridge of the leading vehicle _VF from the amplitude of the vibration component specific to the resonant bridge of the trailing vehicle _VL , and calculates the difference in the amplitude of the vibration component specific to the resonant bridge. As a result, as shown in Fig. 10(D), the difference calculation unit 4e calculates the difference in the amplitude of the vibration component specific to the resonant bridge of the leading vehicle _VF and the trailing vehicle _VL , and outputs the difference in the amplitude of the vibration component specific to the resonant bridge to the resonance detection unit 4f as difference data.

In S500, the control unit 4j commands the resonance detection unit 4f to detect resonance of the short-span bridge _B3 . As a result, the resonance detection unit 4f calculates a resonance bridge detection index RDI, and evaluates whether or not the short-span bridge _B3 is resonating based on the resonance bridge detection index RDI. When the resonance detection unit 4f outputs the detection result of whether or not the short-span bridge _B3 is resonating to the control unit 4j as detection result data, the control unit 4j outputs this detection result data to the detection result data storage unit 4g, and this detection result data is stored in the detection result data storage unit 4g.

In S600, the control unit 4j commands the display unit 4i to display the detection result. The control unit 4j reads out the detection result data from the detection result data storage unit 4g, and outputs the detection result data to the display unit 4i. As a result, the display unit 4i displays on the screen the detection result of whether or not resonance is occurring in the short span bridge _B3 .

The bridge resonance detection method, the bridge resonance detection device, and the bridge resonance detection program according to the first embodiment of the present invention have the following effects.
(1) In this first embodiment, the resonance detection unit 4f detects a short-span bridge _B3 that resonates at an Nth order (N is an integer of 2 or more) based on measurement data _D1 required for detecting a resonating bridge measured from the train T side. For example, in the conventional techniques 1 and 2, it is possible to detect a bridge B in which a single wave of vibration is excited and a primary resonance occurs every time a vehicle passes, but it is not possible to detect a short-span bridge _B3 in which a three-wave vibration is excited and a tertiary resonance occurs every time a vehicle passes. In this first embodiment, the measurement data _D1 required for detecting a resonating bridge measured on the train T side is measured from the train T side, and it is possible to accurately detect a short-span bridge _B3 that resonates at an Nth order based on the measurement data _D1 .

(2) In the first embodiment, the resonance detection unit 4f detects the short-span bridge _B3 that resonates third-order based on the measurement results of the acceleration measurement device 2 that measures the vertical vibration acceleration of the train T from the train T side. Therefore, by using the vehicle body acceleration, which is the vehicle measurement data, the wavelength component specific to the short-span bridge _B3 can be easily detected as the vehicle body vertical acceleration based on the vibration characteristics of the vehicles _VF and _VL . As a result, by using the measurement data _D1 measured by the acceleration measurement device 2 of the train T running on the bridge B, the short-span bridge _B3 can be extracted with high accuracy. For example, by using the vibration acceleration sensors installed on the front and rear vehicles _VF and _VL of many Shinkansen commercial trains, the short-span bridge _B3 that resonates third-order can be easily detected from the vehicle with high accuracy without omission, and the range of application can be greatly expanded. In addition, for example, the wavelength component specific to the resonating bridge can be emphasized by filter processing, and the wavelength component specific to the resonating bridge can be identified, thereby improving the detection accuracy of the resonating bridge. As a result, by performing waveform processing that emphasizes the vibration component of 1/3 of the vehicle length _L , it is possible to reduce the effects of various errors, such as simple measurement errors and position identification errors caused by position deviations due to changes in the distance from the leading vehicle _VF to the trailing vehicle _VL .

(3) In this first embodiment, the acceleration measuring device 2 measures the vertical vibration acceleration in the front and rear of the train T, and the resonance detection unit 4f detects the resonance of the short-span bridge _B3 based on the measurement results of the acceleration measuring device 2 in the front of the train T and the measurement results of the acceleration measuring device 2 in the rear of the train T. Therefore, by detecting and monitoring the resonant bridge frequently and comprehensively using on-board measurement data, it is possible to efficiently maintain and manage the resonant bridge without making additional capital investments in the high-speed railway. In addition, since the same acceleration measuring device 2 is used in the leading car _VF and the trailing car _VL , the variance of the measurement errors of the leading car _VF and the trailing car _VL can be made the same in principle.

(4) In this first embodiment, the acceleration measuring device 2 measures the vertical vibration acceleration of the car bodies of the leading car _VF and the trailing car _{VL of the train T.} Therefore, by using the acceleration measuring device 2 mounted on the leading and trailing cars of a commercial train that runs daily, the state of railway bridges can be grasped easily and frequently, and the presence or absence of resonance of a large number of railway bridges can be efficiently and comprehensively inspected by one run. For example, by using the acceleration sensors installed on the car bodies of the leading and trailing cars of many commercial trains such as the Shinkansen, a short-span bridge _B3 that resonates third-order can be easily detected from on board, and the range of application for detecting resonating bridges can be significantly expanded.

(5) In the first embodiment, the vibration component extracting unit 4c extracts vibration components specific to the resonating bridge based on the measurement results of the acceleration measuring device 2, and the vibration component extracting unit 4c extracts the vibration having _1/3 of the vehicle length _L of the vehicles _VF and VL as the vibration component specific to the resonating bridge. Therefore, for example, the wavelength component specific to the short-span bridge _B3 that resonates third order can be emphasized by filter processing, and the wavelength component specific to the short-span bridge _B3 can be identified, thereby improving the detection accuracy of the resonating bridge. As a result, by performing waveform processing that emphasizes the vibration component of 1/3 of the vehicle length _L , the effects of various errors such as simple measurement errors and position identification errors caused by position shifts due to changes in the distance from the leading vehicle _VF to the trailing vehicle _VL can be reduced.

(6) In this first embodiment, the vibration amplitude estimation unit 4d estimates the amplitude of the vibration component specific to the resonating bridge measured at the front and rear of the train T. In addition, in this first embodiment, the difference calculation unit 4e calculates the difference in the amplitude of the vibration component specific to the resonating bridge measured at the front and rear of the train T, and the resonance detection unit 4f detects the resonance of the short-span bridge _B3 based on the difference in the amplitude of the vibration component specific to the resonating bridge. For this reason, for example, by making the wavelength longer by envelope processing, it is possible to stabilize against the error of the positional deviation of the leading vehicle _VF and the trailing vehicle _VL , and the measurement error component can be offset by the envelope processing. As a result, it is possible to expect a high effect of removing the measurement error component by the envelope processing. In addition, the component specific to the short-span bridge _B3 , which is included in the vertical acceleration of the leading vehicle _VF but not included in the vertical acceleration of the trailing vehicle _VL , can be easily extracted by performing differential processing of the vertical acceleration of the leading vehicle _VF and the vertical acceleration of the trailing vehicle _VL . Furthermore, by differentially processing many vibration components other than the vibration of the short-span bridge _B3 that are mixed into the vertical acceleration measured by the leading car _VF and the trailing car _VL , track irregularities other than the vibration components of the short-span bridge _B3 can be largely cancelled, and the resonating bridge can be extracted with high accuracy. For example, the leading car acceleration data _D11 and the trailing car acceleration data _D12 contain track irregularities, vehicle vibrations, measurement noises, and other components caused by components other than the resonating bridge, in addition to dynamic bridge responses. In this first embodiment, the difference between the two vertical accelerations measured at different positions on the train can offset and largely reduce components caused by track irregularities, vehicle vibrations, measurement noises, and other components caused by components other than the resonating bridge.

(7) In this first embodiment, the short-span bridge _B3 that resonates third-order is detected in the resonance detection procedure based on the measurement results of the acceleration measuring device 2 that measures the vertical vibration acceleration of the train T from the train T side. For this reason, a resonance detection program can be implemented in an existing track maintenance management database system and executed on the track maintenance management database system. In addition, the resonance detection program can be easily added to an existing track maintenance management database system as an optional function. As a result, any operator who maintains and manages the track based on the vehicle body vibration acceleration can easily apply this at low cost without introducing new sensors or databases.

Second Embodiment
In the following, the same parts as those shown in FIGS. 1 to 13 are denoted by the same reference numerals and detailed description thereof will be omitted.
The second embodiment is different from the first embodiment in that the vertical accelerations of the bogies _T1 and _T2 are measured by the acceleration measuring device 2 as shown in FIG. 13 to detect the resonance of the short-span bridge _B3 . The acceleration measuring device 2 measures the vertical accelerations of the bogie _T1 of the leading vehicle _VF and the bogie _T2 of the trailing vehicle _VL . The acceleration detecting unit 2a detects the vertical accelerations (vertical vibration accelerations) of the bogie (first bogie) _T1 of the vehicle _VF of the train T, and the acceleration detecting unit 2b detects the vertical accelerations (vertical vibration accelerations) of the bogie (second bogie) _T2 of the vehicle _VL of the train T. The acceleration detecting units 2a and 2b can use, for example, bogie acceleration sensors for monitoring track conditions mounted on high-speed railway vehicles. The acceleration detecting units 2a and 2b are installed, for example, on the upper parts of the axle boxes of the bogies _T1 and _T2 .

The resonance detection device 4 performs signal processing (filtering and envelope processing) to emphasize vibration components specific to a resonant bridge based on the bogie vertical accelerations measured by the bogies _T1 , _T2 of the leading vehicle _VF and the trailing vehicle _VL of the train T, and performs differential processing of the leading vehicle VF and the trailing vehicle _VL to extract only the vibration component (component of 1/3 of the vehicle length _Lc ) caused by the short-span bridge _B3 by canceling the influence of other vibration components. The resonance detection device 4 detects a resonant bridge based on the presence or absence of a component of 1/3 of the vehicle length _Lc mixed in the _bogie vertical acceleration of the trailing vehicle VL of the train T passing over the resonant bridge. The resonance detection device 4 performs envelope processing _on the bogie vertical acceleration waveforms after filtering in order to realize robust differential processing against position synchronization errors of the leading vehicle _VF and the trailing vehicle _VL and measurement errors of the acceleration sensors. The resonance detection device 4 converts the 1/3 vehicle length L _C component specific to a resonating bridge, contained in the bogie vertical acceleration, into a dominant half-sine wave component corresponding to the span length L _b of the short-span bridge B ₃ through filter processing and envelope processing. The resonance detection device 4 performs filter processing and envelope processing on the two bogie vertical accelerations measured by the leading vehicle V _F and the trailing vehicle V _L , and then cancels out vibration components other than resonance through differential processing in which the leading vehicle V _F is subtracted from the trailing vehicle V _L. This second embodiment has the same effects as the first embodiment.

Third Embodiment
The third embodiment is different from the first and second embodiments in that the track irregularity is measured from the leading vehicle _F and the trailing vehicle _VL by track irregularity measuring devices 2A and 2B as shown in Fig. 14 to detect resonance of the short-span bridge _B3 . The track R shown in Fig. 14 includes a pair of left and right rails _R1 and _R2 for guiding the wheels of a train T as shown in Fig. 16. The resonance detection system 1 shown in Figs. 14 and 15 is a system for detecting resonance of the short-span bridge _B3 on which the train T runs. As shown in Fig. 15, the resonance detection system 1 includes track irregularity measuring devices 2A and 2B, a communication device 3, a resonance detection device 4, and the like. The resonance detection system 1 transmits the measurement results of the track irregularity measuring devices 2A and 2B to the resonance detection device 4 by the communication device 3, and detects resonance of the short-span bridge _B3 based on the measurement results of the track irregularity measuring devices 2A and 2B.

The track irregularity measurement devices 2A, 2B shown in Fig. 14 to Fig. 16 measure the measurement data (vehicle measurement data) _D2 required for detecting a resonating bridge from the train T side. The track irregularity measurement devices 2A, 2B measure the track irregularity on a short-span bridge _B3 as the measurement data _D2 required for detecting a resonating bridge. As shown in Fig. 14, the track irregularity measurement device 2A is arranged on the bogie _T2 on the rear side in the traveling direction of the leading vehicle _VF of the train T, and the track irregularity measurement device 2B is arranged on the bogie _T1 on the front side in the traveling direction of the trailing vehicle _VL of the train T. The track irregularity measurement device 2A measures the track irregularity in front of the train T, and the track irregularity measurement device 2B measures the track irregularity in the rear of the train T. The track irregularity measurement devices 2A, 2B measure the track irregularity while moving on the track R together with the train T. Here, track irregularity (pathway irregularity) refers to a phenomenon in which the track R, which is the road surface on which the train T runs, gradually changes due to repeated passing of the train T, causing a change in the longitudinal shape of the rails _R1 , _R2 shown in Fig. 16, and is also called track irregularity or track irregularity. Both track irregularity measuring devices 2A, 2B have the same structure. As shown in Fig. 16, the track irregularity measuring devices 2A, 2B include a gyro 2h, an acceleration detector 2i, laser displacement meters 2j, 2k, a track irregularity calculator 2m, a travel distance calculator 2n, a measurement data memory 2p, a measurement data transmitter 2q, and a controller 2r.

The track displacement measuring devices 2A and 2B shown in FIGS. 14 to 16 are, for example, on-board track irregularity measuring devices using the inertial arrow method that have been introduced to some high-speed railway trains, and are bogie-mounted track displacement measuring devices (inertial arrow measuring devices) mounted on the bogies T ₁ and T ₂ of commercial trains. Here, the inertial arrow method refers to a method in which the track displacement calculating unit 2m creates a virtual reference line based on the displacement of the vehicles V _F and V _L calculated by the track displacement calculating unit 2m by integrating the output signals of the gyro 2h and acceleration detecting unit 2i mounted on the vehicles V _F and V _L twice, and the track displacement calculating unit 2m calculates the displacement amount from this virtual reference line to the rails R ₁ and R ₂ as the track displacement. In the track displacement measuring devices 2A and 2B, the track displacement calculating unit 2m performs inertial measurement to estimate the position (bogie displacement) of the measuring device at each time point by integrating the output signals of the gyro 2h and acceleration detecting unit 2i twice. In the track displacement measuring devices 2A, 2B, the track displacement calculation unit 2m measures the track displacement with the vibrations of the bogies _T1 , _T2 canceled out by subtracting the bogie displacement (absolute position in space of the device main body) inertial measured by the gyro 2h and acceleration detection unit 2i from the relative displacement (left and right rail positions) between the track R directly below the bogie and the bogies _T1 , _T2 measured by the laser displacement meter 2j.

The gyro 2h shown in Fig. 16 is a device that measures the angular acceleration of the bogies _T1 , _T2 . The acceleration detection unit 2i is a device that detects the acceleration of the bogies _T1 , _T2 . The laser displacement meter 2j is a device that irradiates a laser beam onto the top surfaces of the left and right rails _R1 , _R2 , receives the reflected laser beam, and measures the displacement from the bogies _T1 , _T2 to the left and right rails _R1 , _R2 . The laser displacement meter 2k is a device that irradiates a laser beam onto the top side surfaces of the left and right rails _R1 , _R2 , receives the reflected laser beam, and measures the displacement from the bogies _T1 , _T2 to the left and right rails _R1 , _R2 . The track displacement calculation unit 2m is a means for calculating the track displacement of the track R. The track deviation calculation unit 2m calculates the track deviation of the track R based on the measurement results of the gyro 2h, the acceleration detection unit 2i and the laser displacement meters 2j and 2k, and outputs the calculated track deviation data D ₂₁ to D ₂₅ to the control unit 2r.

The running distance calculation unit 2n is a means for calculating the running distance of the train T. For example, the running distance calculation unit 2n receives absolute position information output by an ATS on-board coil of an automatic train stop device (ATS) installed at a specific point on the track R to detect the absolute position of the train T, and calculates the running distance of the train T by integrating distance pulse signals output by a tachograph that detects the speed of the train T until the train T reaches the next ATS ground coil. The running distance calculation unit 2n outputs the running distance (movement distance) of the train T from the starting point to the control unit 2r as running distance data D ₂₆ .

The measurement data storage unit 2p is a means for storing various measurement data _D2 measured by the track irregularity measuring devices 2A and 2B. For example, as shown in Fig. 17, the measurement data storage unit 2p is a storage device for storing the track irregularity data _D21 to _D25 calculated by the track irregularity calculation unit 2m and the travel distance data _D26 calculated by the travel distance calculation unit _2n as measurement data (inspection data) D2, and stores the track irregularity data _D21 to _D25 in chronological order in correspondence with the travel distance data _D26 . Here, the track irregularity data _D21 shown in Fig. 17 is data on elevation displacement, which is the vertical displacement of the rails _R1 and _R2 . The track irregularity data _D22 is data on level displacement, which is the difference in height (height difference) between the left and right rails _R1 and _R2 . The track irregularity data _D23 is data on runway irregularity, which is the amount of change in the level of the track R over a certain distance (the twisted state of the track R relative to the plane). The track irregularity data _D24 is data relating to the lateral displacement of the rails _R1 , _R2 . The track irregularity data _D25 is data relating to gauge deviation, which is the change in the distance (gauge) between the left and right rails _R1 , _R2 .

16 is a means for transmitting measurement data _D2 from the track irregularity measuring devices 2A, 2B. The measurement data transmitting unit 2q is a transmitter that transmits the measurement data _D2 from the track irregularity measuring devices 2A, 2B to the resonance detecting device 4 through the communication device 3. The measurement data transmitting unit 2q transmits the measurement data _D2 to the resonance detecting device 4 in real time.

The control unit 2r is a central processing unit (CPU) that controls various operations related to the track deviation measuring devices 2A and 2B. For example, the control unit 2r instructs the gyro 2h and the acceleration detection unit 2i to detect angular acceleration and acceleration, instructs the track deviation calculation unit 2m to calculate track deviation, outputs the track deviation data _D21 to _D25 output by the track deviation calculation unit 2m to the measurement data storage unit 2p, instructs the travel distance calculation unit 2n to calculate travel distance, outputs the travel distance data _D26 output by the travel distance calculation unit 2n to the measurement data storage unit 2p, instructs the measurement data storage unit 2p to store the track deviation data _D21 to _D25 and the travel distance data _D26 , reads out the measurement data _D2 from the measurement data storage unit 2p and outputs it to the measurement data transmission unit 2q, and instructs the measurement data transmission unit 2q to transmit the measurement data _D2 . The control unit 2r is communicatively connected to the gyro 2h, the acceleration detection unit 2i, the laser displacement meters 2j and 2k, the track displacement calculation unit 2m, the travel distance calculation unit 2n, the measurement data storage unit 2p, and the measurement data transmission unit 2q.

15 transmits measurement data _D2 from the track irregularity measuring devices 2A and 2B to the resonance detection device 4. The communication device 3 transmits the measurement data _D2 from the measurement data transmitting units 2q of the track irregularity measuring devices 2A and 2B to the measurement data receiving unit 4a of the resonance detection device 4.

14 and 15 removes track displacement other than the bridge displacement (bridge displacement component) of the short-span bridge _B3 from the track displacement data _D21 measured by the track displacement measuring devices 2A, 2B, and extracts vibration components specific to the resonating bridge. The resonance detection device 4 detects the resonance of the short-span bridge _B3 from the difference between the amplitude of the vibration component specific to the resonating bridge measured by the leading vehicle _VF and the amplitude of the vibration component specific to the resonating bridge measured by the trailing vehicle _VL .

Next, the detection principle of the bridge resonance detection device according to the third embodiment of the present invention will be described.
The resonance detection device 4 shown in Fig. 14 and Fig. 15 detects the short-span bridge _B3 from the presence or absence of a component of 1/3 of the vehicle length _Lc mixed in the track displacement of the rear vehicle _VL of the train T passing over the short-span bridge _B3 . As shown in Fig. 18, the resonance detection device 4 performs signal processing (filter and envelope processing) to emphasize the vibration component specific to the resonant bridge based on the track displacement (vertical displacement) measured by the front vehicle _VF and the rear vehicle _{VL of the train T} , and performs differential processing of the front vehicle _VF and the rear vehicle _VL to cancel the influence of other vibration components and extract only the vibration component (component of 1/3 of the vehicle length _Lc ) caused by the resonant bridge. The resonance detection device 4 uses the difference value (envelope difference) of the envelope-processed waveform as a detection index, and judges that the short-span bridge _B3 is a resonant bridge when this detection index forms a dominant component corresponding to the span length _Lb of the short-span bridge _B3 over which the train T passes.

(Filtering)
The resonance detection device 4 performs filtering to reduce components other than the 1/3 vehicle length L _C component caused by the short-span bridge B ₃ from among the various components mixed into the track displacement. The resonance detection device 4 extracts the 1/3 vehicle length L _C component mixed into the response of the rear vehicle V _L when passing over the resonant bridge, and identifies the wavelength component (1/3 vehicle length L _C ) unique to the short-span bridge B ₃ that resonates third order.

(Envelope Processing)
The resonance detection device 4 performs envelope processing on the track irregularity after filtering. As shown in Fig. 8, the resonance detection device 4 performs envelope processing to estimate the amplitude of a waveform corresponding to a span length component from the waveform of the dynamic response component zb _,d ( _xp ) extracted by filtering. Assuming that the track irregularity measuring devices 2A, 2B of the leading car _VF and the trailing car _VL are of the same type and that the mixed-in measurement noise is generated in the same way, the resonance detection device 4 converts the evaluation as a waveform to an evaluation as an amplitude amount by envelope processing, thereby canceling out the measurement noise when differential processing is performed, and significantly reducing the measurement noise.

(Differential processing of leading and trailing vehicles)
The resonance detection device 4 eliminates track irregularity excluding bridge displacement and quasi-static deflection components of the short-span bridge _B3 by subtracting track irregularity including bridge displacement measured by the leading vehicle _VF from track irregularity including bridge displacement measured by the trailing vehicle _VL . As shown in Fig. 8, the resonance detection device 4 converts the component of 1/3 of the vehicle length _Lc included in the track irregularity into a dominant component of a half-sine wave shape corresponding to the span length _Lb of the short-span bridge _B3 by filter processing and envelope processing. As shown in Fig. 18, the resonance detection device 4 applies filter processing and envelope processing to the two track irregularities measured by the leading vehicle _VF and the trailing vehicle _VL , and then cancels out components other than resonance by differential processing in which the leading vehicle _VF is subtracted from the trailing vehicle _VL .

The measurement data receiving unit 4a shown in Fig. 15 receives the measurement data _D2 transmitted by the track irregularity measurement devices 2A, 2B. The measurement data receiving unit 4a receives the measurement data _D2 transmitted by the track irregularity measurement devices 2A, 2B through the communication device 3. The measurement data storage unit 4b stores the measurement data _D2 transmitted by the track irregularity measurement devices 2A, 2B. The measurement data storage unit 4b is a storage device that stores, for example, the measurement data _D2 transmitted by the track irregularity measurement devices 2A and 2B in chronological order as shown in Fig. 17.

The vibration component extracting unit 4c shown in Fig. 15 extracts vibration components specific to a resonating bridge based on the measurement results of the track displacement measuring devices 2A and 2B. The vibration component extracting unit 4c extracts vibration components specific to a resonating bridge from the track displacement data _D21 , which is the track displacement in the vertical direction stored in the measurement data storage unit 4b. The vibration component extracting unit 4c extracts vibration components specific to the resonating bridge of the leading vehicle _VF from the measurement results (track displacement waveform) of the track displacement measuring device 2A, and extracts vibration components specific to the resonating bridge of the trailing vehicle _VL from the measurement results (track displacement waveform) of the track displacement measuring device 2B. The vibration component extracting unit 4c passes only vibrations (car length irregularities) whose main component is _1/3 of the car length _Lc from the measurement waveform showing the time change in track displacement including the displacement (bridge response) of the long-span bridge B3, and removes vibrations other than those whose main component is 1/3 of the car length _Lc .

The vibration amplitude estimation unit 4d estimates the amplitude of the vibration component specific to the resonating bridge of the leading vehicle _VF based on the measurement results of the track displacement measurement device 2A, and estimates the amplitude of the vibration component specific to the resonating bridge of the trailing vehicle _VL based on the measurement results of the track displacement measurement device 2B. The vibration amplitude estimation unit 4d estimates the amplitude of vibration having 1/3 of the vehicle length _Lc as the main component by envelope processing. The difference calculation unit 4e calculates the difference in track displacement including bridge displacement of the leading vehicle _VF and the trailing vehicle _VL after bandpass filter processing and envelope processing.

The resonance detection unit 4f detects resonance of the short-span bridge _B3 based on the measurement results of the track irregularity measurement devices 2A and 2B. The resonance detection unit 4f detects resonance of the short-span bridge _B3 based on the measurement results of the acceleration measurement device 2 that measures the vertical acceleration of the leading vehicle _VF and the measurement results of the acceleration measurement device 2 that measures the vertical acceleration of the trailing vehicle VL. The display unit 4i displays _{the track irregularity data D21 to D25} as shown in Fig. 17 on the screen in correspondence with the travel distance data _D26 , and also displays the presence or absence of resonance for each short-span bridge _B3 through which the train T passes in correspondence with the travel distance data _D26 . The control unit 4j shown in Fig. 15, for example, reads out the track irregularity data _D21 from the measurement data storage unit 4b and outputs it to the vibration component extraction unit 4c, or instructs the vibration component extraction unit 4c to extract the vibration component specific to the resonant bridge from the track irregularity data _D21 .

Next, a method for detecting resonance of a bridge according to a third embodiment of the present invention will be described.
FIG. 19 is a graph showing an example of the case where the resonance detection method is applied to the displacement components of a short-span bridge _B3 with a span length of 10 m measured by the leading vehicle _VF and the trailing vehicle _VL . FIG. 19(A) is a graph showing the vertical displacement of the center of the bridge span when a train passes through at train speeds of 200, 230, 250, 270, and 300 km/h. The vertical axis shown in FIG. 19(A) is vertical displacement [m], and the horizontal axis is time [s]. FIG. 19(B) is a graph showing the vertical displacement of the first axle of the leading vehicle _VF and the fourth axle of the trailing vehicle _VL when passing through the bridge. The vertical axis shown in FIG. 19(B) is vertical displacement [mm]. FIG. 19(C) is a graph showing the application result after band pass filter (BPF) processing and envelope processing to the vertical displacement when passing through the bridge. The vertical axis shown in FIG. 19(C) is vertical displacement [mm]. Figure 19(D) is a graph showing the application result after differential processing of the envelope-processed vertical displacement of the first axle of the leading vehicle _VF and the fourth axle of the trailing vehicle _VL . The vertical axis shown in Figure 19(D) is the envelope difference [m/ ^s2 ]. The horizontal axis shown in Figures 19(B) to (D) is the position [m] from the left end of the bridge.

In resonance detection method #100 shown in Fig. 11, track displacement other than the displacement component of the short-span bridge _B3 is removed from track displacement data _D21 measured by track displacement measuring devices 2A, _2B shown in Fig. 14 and 15, and vibration components specific to the resonating bridge are extracted. In resonance detection method #100, resonance of the short-span bridge _B3 is detected from the difference between the amplitude of the vibration component specific to the resonating bridge measured by the leading vehicle VF and the amplitude of the vibration component specific to the resonating bridge measured by the trailing vehicle _VL .

In the vibration component extraction process #110, vibration components specific to a resonating bridge are extracted based on the measurement results of the track displacement measurement devices 2A and 2B. In the vibration component extraction process #110, vibrations having 1/3 of the vehicle length _Lc as the main component are extracted as vibration components specific to a resonating bridge. In the vibration component extraction process #110, as shown in FIG. 19(B), from the track displacement measured by the track displacement measurement device 2A at the bogie _T1 of the leading vehicle _VF and the track displacement measured by the track displacement measurement device 2B at the bogie _T2 of the trailing vehicle _VL , displacement components other than the displacement component of the short-span bridge _B3 are removed by filtering (BPF) processing as shown in FIG. 19(C). As a result, the track displacement of only the bridge displacement measured by the bogie _T1 of the leading vehicle _VF and the track displacement of only the bridge displacement measured by the bogie _T2 of the trailing vehicle _VL are extracted as vibration components specific to a resonating bridge having 1/3 of the vehicle length _Lc as the main component.

In the vibration amplitude estimation step #120, the amplitude of the vibration component specific to the resonant bridge of the leading vehicle _VF is estimated based on the measurement result of the track displacement measurement device 2A, and the amplitude of the vibration component specific to the resonant bridge of the trailing vehicle _VL is estimated based on the measurement result of the track displacement measurement device 2B. In the vibration amplitude estimation step #120, the vibration component specific to the resonant bridge of the leading vehicle _VF and the vibration component specific to the resonant bridge of the trailing vehicle _VL shown in FIG. 19(C) are subjected to envelope processing. As a result, the amplitude of the vibration component specific to the resonant bridge of the leading vehicle _VF and the amplitude of the vibration component specific to the resonant bridge of the trailing vehicle _VL are estimated. In the difference calculation step #130, as shown in FIG. 19(D), the amplitude of the vibration component specific to the resonant bridge of the leading vehicle _VF is subtracted from the amplitude of the vibration component specific to the resonant bridge of the trailing vehicle _VL , and a resonant bridge detection index RDI corresponding to the envelope difference is calculated.

In the resonance detection process #140, resonance of the short-span bridge _B3 is detected based on the measurement results of the track displacement measurement devices 2A and 2B. In the resonance detection process #140, resonance of the short-span bridge B3 is detected based on the measurement results of the track displacement measurement device 2A that measures track displacement in the leading vehicle _VF and the measurement results of the track displacement measurement device 2B that measures track displacement in the trailing vehicle _VL . In the resonance detection process #140, resonance of the short-span bridge _B3 is detected based on the difference in amplitude of _vibration components specific to the resonating bridge of the leading vehicle _VF and the trailing vehicle _VL . In the resonance detection process #140, when the resonating bridge detection index RDI shown in Fig. 19(D) exceeds a predetermined value, it is determined that the short-span bridge _B3 is resonating, and when the resonating bridge detection index RDI is equal to or less than the predetermined value, it is determined that the short-span bridge _B3 is not resonating.

Next, the operation of the bridge resonance detection device according to the third embodiment of the present invention will be described.
In S200 shown in Fig. 12, the control unit 4j reads out from the measurement data storage unit 4b the track irregularity data _D21 measured by the track irregularity measurement device 2A for the leading vehicle _VF and the track irregularity data _D21 measured by the track irregularity measurement device 2B for the trailing vehicle _VL , and outputs these track irregularity data _D21 to the vibration component extraction unit 4c. For this reason, the vibration component extraction unit 4c extracts the vibration component specific to a resonant bridge, whose main component is 1/3 of the vehicle length _Lc , by bandpass filter processing from the waveform of the dynamic displacement _zb,d ( _xp ) of the short-span bridge _B3 shown in Fig. 8.

In S300, the vibration amplitude estimation unit 4d estimates the amplitude of the vibration component specific to the resonating bridge measured by the leading vehicle _VF based on the measurement results of the track displacement measurement device 2A. Also in S300, the vibration amplitude estimation unit 4d estimates the amplitude of the vibration component specific to the resonating bridge measured by the trailing vehicle _VL based on the measurement results of the track displacement measurement device 2B. The vibration amplitude estimation unit 4d performs envelope processing on the waveform of the dynamic displacement z _b,d (x _p ) of the short-span bridge _B3 whose wavelength is 1/3 of the _vehicle length _{L c} shown in Fig. 8. In S400, the difference calculation unit 4e subtracts the amplitude of the vibration component specific to the resonating bridge of the leading vehicle _VF from the amplitude of the vibration component specific to the resonating bridge of the trailing vehicle VL, and calculates the difference in the amplitude of the vibration component specific to the resonating bridge.

In S500, based on the measurement results of the track displacement measuring devices 2A and 2B, the control unit 4j commands the resonance detection unit 4f to detect resonance of the short-span bridge _B3 . As a result, the resonance detection unit 4f calculates the resonance bridge detection index RDI, and evaluates whether or not the short-span bridge _B3 is resonating based on the resonance bridge detection index RDI.

The bridge resonance detection method, the resonance detection device, and the bridge resonance detection program according to the third embodiment of the present invention have the following effects in addition to the effects of the first and second embodiments.
(1) In this third embodiment, the resonance detection unit 4f detects the short-span bridge _B3 that resonates third-order based on the measurement results of the track displacement measuring devices 2A, 2B that measure the track displacement on the short-span bridge _B3 from the train T side. Therefore, by using the track displacement data _D21 measured by the track displacement measuring devices 2A, 2B of the train T running on the bridge B, the resonance of the short-span bridge _B3 can be extracted with high accuracy. For example, the resonance of the short-span bridge _B3 can be easily detected by using the measurement results of the commercial vehicle inspection that measures the track displacement from a commercial train. In addition, a resonating bridge can be easily detected based on the dynamic track displacement measured by the multiple cars _VF , _VL that make up the running train.

(2) In this third embodiment, the track displacement measuring devices 2A and 2B measure track displacement at the front and rear of the train T, and the resonance detection unit 4f detects the resonance of the short-span bridge _B3 based on the measurement results of the track displacement measuring device 2A at the front of the train T and the measurement results of the track displacement measuring device 2B at the rear of the train T. For example, in some high-speed railways in Japan, the track displacement such as the height of the rails _R1 and _R2 is measured in the leading and trailing cars of a commercial train. In this third embodiment, the state of the railway bridge can be grasped frequently and easily by using the track displacement measuring devices 2A and 2B mounted on the leading and trailing cars of a commercial train that runs daily, and the presence or absence of resonance of a huge number of railway bridges can be efficiently and comprehensively inspected by one run. As a result, the resonant bridges can be efficiently maintained and managed by the frequent and comprehensive detection and monitoring of resonant bridges using on-board measurement data without additional capital investment in the high-speed railway. In addition, since the same track irregularity measuring devices 2A, 2B are used for the leading vehicle _VF and the trailing vehicle _VL , the variances of the measurement errors of the leading vehicle _VF and the trailing vehicle _VL can, in principle, be made to be approximately the same.

(3) In this third embodiment, the track displacement measuring devices 2A, 2B measure the displacement of the track R from the leading car _VF and the trailing car _VL of the train T. Therefore, for example, by utilizing the track displacement measuring devices 2A, 2B installed on the bodies of the leading car and the trailing car, the short-span bridge _B3 that resonates third-order can be easily detected from on-board the train, and the range of application for detecting resonating bridges can be significantly expanded.

(4) In the third embodiment, the vibration component extracting unit 4c extracts vibration components specific to the resonating bridge based on the measurement results of the track displacement measuring devices 2A and 2B, and extracts the vibrations having 1/3 of the vehicle length _L of _the vehicles _VF and VL as the vibration components specific to the resonating bridge. For this reason, for example, the wavelength components specific to the short-span bridge _B3 that resonates third-order can be emphasized by filter processing, and the wavelength components specific to the short-span bridge _B3 can be identified, improving the detection accuracy of the resonating bridge. As a result, by performing waveform processing that emphasizes the vibration components of 1/3 of the vehicle length _L , the effects of various errors such as simple measurement errors and position identification errors caused by position deviations due to changes in the distance from the leading vehicle _VF to the trailing vehicle _VL can be reduced.

(5) In this third embodiment, the vibration amplitude estimation unit 4d estimates the amplitude of the vibration component specific to the resonating bridge measured at the front and rear of the train T. In addition, in this third embodiment, the difference calculation unit 4e calculates the difference in the amplitude of the vibration component specific to the resonating bridge measured at the front and rear of the train _T , and the resonance detection unit 4f detects the resonance of the short-span bridge _B3 based on the difference in the amplitude of the vibration component specific to the resonating bridge. Therefore, by performing difference processing on many vibration components other than the vibration of the short-span bridge _B3 that are mixed in the track irregularity measured by the leading vehicle _VF and the trailing vehicle VL, it is possible to largely cancel the track irregularity other than the vibration component of the short-span bridge _B3 . For example, the track irregularity data _D21 contains irregularities caused by things other than the bridge and track structure displacements in addition to dynamic bridge responses. In this third embodiment, assuming that irregularities caused by factors other than the bridge and displacement of the track structure do not change when measured at two different points in time, the difference between two track irregularities measured at different positions on the train and converted into a function of position can cancel irregularities caused by factors other than the bridge and displacement of the track structure. As a result, short-span bridge _B3 can be easily detected from the difference in amplitude of the vibration components specific to a resonating bridge, and the resonating bridge can be extracted with high accuracy by canceling out components other than the displacement components of short-span bridge _B3 through difference processing.

Fourth Embodiment
The fourth embodiment is different from the first to third embodiments, and is an embodiment in which the vertical acceleration of the vehicle bodies of the leading vehicle _F and the trailing vehicle _VL of the magnetic levitation railway are measured by an acceleration measuring device 2 as shown in FIG. 20 to detect the resonance of the short-span bridge _B3 . The guideway W shown in FIG. 20 is a ground facility that constitutes a space in which the vehicles _VF , _VM , and _VL of the magnetic levitation railway run. The guideway W corresponds to the track R shown in FIG. 2, FIG. 13, and FIG. 14, and has a cross-sectional shape of a substantially U-shaped recess when cut by a plane perpendicular to the longitudinal direction of the guideway W. The guideway W includes a running path _W1 on which the support wheels of the vehicles _VF , _VM , and _VL run, and substantially vertical side walls _W2 formed on both sides of the running path _W1 . The guideway W functions as a support part that supports the vehicles _VF , _VM, and _VL , and also functions as a guide part that prevents the vehicles _VF , _VM , and _VL from deviating in the horizontal direction. The guideway W supports propulsion coils that provide propulsive forces to the vehicles _VF , _VM , and _VL , and levitation and guidance coils that generate levitation and guidance forces for the vehicles _VF , _VM , and _VL .

The train T is a moving body that moves along the guideway W. The train T is a magnetic levitation railway vehicle that moves on a bridge B. The train T runs with cars _VF , _VM , and _VL levitated by magnetic attraction and magnetic repulsion. The train T is equipped with a superconducting magnet M that generates a strong magnetic field. The acceleration detection units 2a and 2b detect vertical acceleration in front of the leading car _VL and behind the trailing car _VL . The acceleration detection unit 2a is installed, for example, on the car body floor on the front side in the traveling direction of the leading car _VL , and the acceleration detection unit 2b is installed on the car body floor on the rear side in the traveling direction of the trailing car _VL . This fourth embodiment has the same effects as the first to third embodiments.

Fifth Embodiment
The fifth embodiment differs from the first to third embodiments in that it detects resonance of the short-span bridge _B3 by measuring guideway displacement from the leading car _F and the trailing car _VL of a magnetic levitation railway using guideway displacement measuring devices 2C, 2D as shown in Fig. 21. The resonance detection system 1 includes guideway displacement measuring devices 2C, 2D, etc., as shown in Fig. 21 and Fig. 22. The resonance detection system 1 transmits the measurement results of the guideway displacement measuring devices 2C, 2D to the resonance detection device 4 via the communication device 3, and detects resonance of the short-span bridge _B3 based on the measurement results of the guideway displacement measuring devices 2C, 2D.

The guideway displacement measuring devices 2C and 2D are devices that measure the measurement data _D2 required for detecting a resonant bridge from the train T side. The track displacement measuring devices 2A and 2B measure the guideway displacement on the bridge B as the measurement data _D2 required for detecting a resonant bridge. Here, the guideway displacement (passageway displacement) is the error of the position and dimensions of the guideway W at the site relative to the design position and basic dimensions of the guideway W. The guideway displacement includes elevation displacement, alignment displacement, level displacement, planarity displacement, and inner surface distance displacement, as with the track displacement, and is also called guideway irregularity or guideway deviation. As shown in FIG. 21, the guideway displacement measuring device 2C is disposed on the superconducting magnet M on the rear side of the traveling direction of the leading car _VF of the train T, and the guideway displacement measuring device 2D is disposed on the superconducting magnet M on the front side of the traveling direction of the trailing car _VL of the train T. The guideway displacement measuring device 2C measures the guideway displacement ahead of the train T, and the guideway displacement measuring device 2D measures the guideway displacement behind the train T. The guideway displacement measuring devices 2C, 2D measure the guideway displacement while moving on the guideway W together with the train T. The guideway displacement measuring devices 2C, 2D both have the same structure, and are similar in structure to the track displacement measuring devices 2A, 2B shown in Figs.

The resonance detection device 4 shown in Figures 21 and 22 removes guideway displacements other than the displacement component (bridge displacement) of the short-span bridge _B3 from the guideway displacement data measured by the guideway displacement measurement devices 2C, 2D, and extracts vibration components specific to the resonant bridge. The measurement data receiving unit 4a shown in Figure 22 receives the measurement data _D2 transmitted by the guideway displacement measurement devices 2C, 2D. The measurement data storage unit 4b stores the measurement data _D2 transmitted by the guideway displacement measurement devices 2C, 2D.

The vibration component extraction unit 4c shown in Fig. 22 extracts vibration components specific to resonant bridges based on the measurement results of the guideway displacement measurement devices 2C and 2D. The vibration component extraction unit 4c extracts vibration components specific to resonant bridges from guideway displacement data, which is the vertical guideway displacement stored in the measurement data storage unit 4b. The vibration amplitude estimation unit 4d estimates the amplitude of the vibration component specific to the resonant bridge measured by the leading vehicle _VF based on the measurement results of the guideway displacement measurement device 2C, and estimates the amplitude of the vibration component specific to the resonant bridge measured by the trailing vehicle _VL based on the measurement results of the guideway displacement measurement device 2D.

The resonance detection unit 4f detects resonance of the short-span bridge _B3 based on the measurement results of the guideway displacement measuring devices 2C, 2D. The resonance detection unit 4f detects resonance of the short-span bridge _B3 based on the measurement results of the guideway displacement measuring device 2C, which measures guideway displacement in the leading vehicle VF, and the measurement results of the guideway displacement measuring device 2D, _which measures guideway displacement in the trailing vehicle _VL .

In the resonance detection method #100 shown in Fig. 11, guideway displacements other than the displacement component of the short-span bridge _B3 are removed from the guideway displacement data measured by the guideway displacement measuring devices 2C and 2D shown in Fig. 21 and Fig. 22, and vibration components specific to the resonating bridge are extracted. In the vibration component extraction step #110, vibration components specific to the resonating bridge are extracted based on the measurement results of the guideway displacement measuring devices 2C and 2D. In the vibration component extraction step #110, displacement components other than the displacement component of the short-span bridge _B3 are removed by filtering from the guideway displacement measured by the guideway displacement measuring device 2C on the leading vehicle _VF and the guideway displacement measured by the guideway displacement measuring device 2D on the trailing vehicle _VL . In the resonance detection step #140, the resonance of the short-span bridge _B3 is detected based on the measurement results of the guideway displacement measuring devices 2C and 2D. In the resonance detection process #140, resonance of the short-span bridge _B3 is detected based on the measurement results of the guideway displacement measuring device 2C that measures the guideway displacement on the leading vehicle VF and the measurement results of the guideway displacement measuring device _2D that measures the guideway displacement on the trailing vehicle _VL . This fifth embodiment has the same effects as the first to fourth embodiments.

Other Embodiments
The present invention is not limited to the above-described embodiment, and various modifications and variations are possible as described below, which are also within the scope of the present invention.
(1) In this embodiment, the bridge B is a rigid-frame viaduct, but the present invention can also be applied to the bridge B being a girder-type viaduct. In addition, in this embodiment, the resonance detection unit 4f detects the third-order resonance (resonance whose vibration mode is the third bending mode) of the short-span bridge _B3 , but the present invention can also be applied to the case where the resonance detection unit 4f detects the Nth-order resonance (resonance whose vibration mode is the Nth bending mode (N is an integer of 2 or more)) of the short-span bridge _{B3 .} For example, the resonance detection unit 4f can detect the second-order resonance (resonance whose vibration mode is the second bending mode) of the short-span bridge _B3 or the fourth-order or higher resonance (resonance whose vibration mode is the fourth bending mode or higher) of the short-span bridge B3. In this case, the vibration component extractor 4c extracts from the waveform of the dynamic response component _zb,d ( _xp ) of the short-span bridge _B3 a vibration component whose main component is 1/N (N is an integer equal to or greater than 2) of the vehicle length _Lc as a vibration component sin(2Nπx/ _Lc + _θres ) (N is an integer equal to or greater than ₂ ) specific to a resonating bridge. Furthermore, in this embodiment, an example has been described in which resonance of the short-span bridge _B3 is detected based on the car body acceleration, bogie acceleration, or track displacement measured on the vehicles _VF , _VL sides as the measurement data (vehicle measurement data) _D1 , _D2 required to detect a resonating bridge, but the present invention can also be applied to cases in which resonance of the short-span bridge _B3 is detected based on measurement data other than these measurement data _D1 , D2.

(2) In this embodiment, the short-span bridge _B3 is a concrete bridge, but the present invention can be applied to the short-span bridge _B3 is a steel bridge. In addition, in this embodiment, the acceleration measuring device 2, the track displacement measuring devices 2A, 2B, and the guideway displacement measuring devices 2C, 2D are arranged in front and behind the train T, but the locations of the acceleration measuring device 2, the track displacement measuring devices 2A, 2B, and the guideway displacement measuring devices 2C, 2D are not limited. For example, the present invention can be applied to the case where the acceleration measuring device 2, the track displacement measuring devices 2A, 2B, and the guideway displacement measuring devices 2C, 2D are arranged at any positions equidistant to the front and rear of the center part O of the train T.

(3) In this embodiment, the train T is a 12-car train, but the present invention can be applied to trains T that are 8, 10, or 16 cars. In addition, in this embodiment, the train T has a vehicle length _Lc of 25 m and the short-span bridge _B3 has a span length _Lb of 10 m, but the present invention is not limited to these vehicle length _Lc and span length _Lb. For example, the present invention can be applied to trains _T that are 20 m and span length _Lb of 10 m.

(4) In the first embodiment, an example has been described in which the acceleration measuring devices 2 are disposed on the vehicle bodies on the front side of the traveling direction of the vehicle _VF and on the rear side of the traveling direction of the _vehicle VL, but the present invention can also be applied to cases in which the acceleration measuring devices 2 are disposed on the vehicle bodies on the rear side of the traveling direction of the vehicle _VF and on the front side of the traveling direction of the vehicle _VL . Similarly, in the second and third embodiments, an example has been described in which the acceleration measuring devices 2 or track irregularity measuring devices 2A, _2B are disposed on the bogie _T1 on the front side of the traveling direction of the _{vehicle VF} and on the bogie T2 on the rear side of the traveling direction of the vehicle _VL , but the present invention can also be applied to cases in which the acceleration measuring devices ₂ or track irregularity measuring devices 2A, 2B are disposed on the bogie T2 on the rear side of the traveling direction of the vehicle _VF and on the bogie _T1 on the front side of the traveling direction of the vehicle VL.

(5) In the first and second embodiments, the acceleration measuring device 2 continuously measures the vertical acceleration from the starting point to the end point. However, the present invention can also be applied to the case where the acceleration measuring device 2 measures the vertical acceleration only within the section on the bridge B. Similarly, in the third embodiment, the track displacement measuring devices 2A and 2B continuously measure the track displacement from the starting point to the end point. However, the present invention can also be applied to the case where the track displacement measuring devices 2A and 2B measure the track displacement only within the section on the bridge B. Furthermore, in the first and second embodiments, the track displacement measuring devices 2A to 2C are inertial forward arrow measuring devices. However, the present invention can also be applied to measuring devices other than inertial forward arrow measuring devices.

(6) In the first to third embodiments, the train T is a Shinkansen vehicle that runs on a Shinkansen line. However, the present invention can also be applied to conventional line vehicles that run on conventional lines, or vehicles for Shinkansen-conventional line through operation that can run on both the Shinkansen and conventional lines. In addition, in the first to third embodiments, the train T is a commercial train. However, the present invention can also be applied to an inspection train that is organized for the purpose of testing and inspecting vehicles, tracks, or overhead lines. For example, the present invention can also be applied to a track inspection vehicle such as an electric track comprehensive test vehicle that has the function of inspecting the condition of ground equipment.

(7) In the first to third embodiments, the car body of each car _VF , _VM , _VL of the train T is supported by two bogies _T1 , _T2 , but the present invention can also be applied to a case where adjacent cars _VF , _VM , _VL are supported by an articulated bogie. Furthermore, in the first to third embodiments, the position detection unit 2d and the running distance calculation unit 2n calculate the travel distance of the train T based on the output signal of the tachograph and the output signal of the ATS on-board unit, but the present invention is not limited to such a calculation method. For example, the present invention can also be applied to a case where the running distance of the train T is calculated by using a GPS (Global Positioning System) or an autonomous navigation device (gyro) in combination.

(8) In the fifth embodiment, an example has been described in which the guideway displacement measurement device 2C is disposed _on the superconducting magnet M at the rear of the vehicle _VF in the traveling direction, and the guideway displacement measurement device 2D is disposed on the superconducting magnet M at the front of the vehicle _VL in the traveling direction, but the present invention can also be applied to a case in which the guideway displacement measurement device 2C is disposed on the superconducting magnet M at the front of the vehicle _VF in the traveling direction, and the guideway displacement measurement device 2D is disposed on the superconducting magnet M at the rear of the vehicle VL in the traveling direction. Also, in the fifth embodiment, an example has been described in which the guideway displacement is measured by the guideway displacement measurement devices 2C, 2D of the vehicles _VF , _VL , but the present invention can also be applied to a case in which resonance of the short-span bridge _B3 is detected based on the measurement results of the guideway displacement measurement devices 2C, 2D of a guideway inspection vehicle that measures guideway displacement while traveling along the guideway W.

1 Resonance detection system 2 Acceleration measuring device 2A, 2B Track displacement measuring device (pathway displacement measuring device)
2C, 2D Guideway displacement measuring device (passageway displacement measuring device)
2a, 2b Acceleration detection unit 2h Gyro 2i Acceleration detection unit 2j, 2k Laser displacement meter 3 Communication device 4 Resonance detection device 4c Vibration component extraction unit 4d Vibration amplitude estimation unit 4e Difference calculation unit 4f Resonance detection unit R Track (pathway)
_R1 , _R2 rails B bridge _B3 short span bridge T train (moving object)
V _F car (leading car (front))
V _M car (middle car)
V _L vehicle (rear vehicle (rear))
T ₁ cart (first cart)
T ₂ cart (second cart)
_D1 , _D2 measurement data _D11 Leading vehicle acceleration data _D12 Rear vehicle acceleration data _D21 to _D25 Track irregularity data _D26 Travel distance data
RDI Resonant Bridge Detection Index W Guideway (passageway)
W ₁ Running path W ₂ Side wall

Claims (16)

A method for detecting resonance of a bridge over which a moving object moves, comprising:
a resonance detection step of detecting an Nth-order resonance (N is an integer of 2 or more) of a short-span bridge having a span length shorter than the vehicle length of the vehicles that make up the moving body , based on the vertical vibration acceleration of the moving body measured from the moving body side ;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to claim 1,
the resonance detection step includes a step of detecting resonance of the short-span bridge based on a measurement result of an acceleration measuring device that measures vertical vibration acceleration of the moving body from the moving body side;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to claim 2,
the acceleration measuring device measures vertical vibration acceleration in the front and rear of the moving body,
the resonance detection step includes a step of detecting resonance of the short-span bridge based on a measurement result of the acceleration measuring device in front of the moving body and a measurement result of the acceleration measuring device in rear of the moving body;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to claim 3,
The acceleration measuring device measures the vertical vibration acceleration of the car body or the bogie of the leading car and the trailing car which compose the moving body;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to any one of claims 2 to 4,
A vibration component extraction step of extracting a vibration component specific to a resonant bridge based on a measurement result of the acceleration measuring device,
the vibration component extraction step includes a step of extracting a vibration having a main component of 1/N of a vehicle length of a vehicle that composes the moving body as a vibration component specific to the resonant bridge;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to claim 1,
the resonance detection step includes a step of detecting resonance of the short-span bridge based on a measurement result of a passage displacement measuring device that measures a passage displacement on the bridge from the moving object side;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to claim 6,
The passage displacement measuring device measures passage displacement in front of and behind the moving body,
the resonance detection step includes a step of detecting resonance of the short-span bridge based on a measurement result of the passage displacement measurement device in front of the moving body and a measurement result of the passage displacement measurement device in rear of the moving body;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to claim 7,
the passage displacement measuring device measures passage displacement from a leading vehicle and a trailing vehicle that constitute the moving body;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to any one of claims 6 to 8,
A vibration component extraction step of extracting a vibration component specific to a resonant bridge based on a measurement result of the passage displacement measuring device,
the vibration component extraction step includes a step of extracting a vibration having a main component of 1/N of a vehicle length of the vehicle that constitutes the moving body as a vibration component specific to the resonant bridge;
A method for detecting resonance in a bridge, comprising: The method for detecting resonance of a bridge according to claim 5 or 9,
a vibration amplitude estimation step of estimating the amplitude of a vibration component specific to the resonant bridge measured in front of and behind the moving body;
and a difference calculation step of calculating a difference in amplitude of a vibration component specific to the resonant bridge measured at the front and rear of the moving body ,
the resonance detection step includes a step of detecting resonance of the short-span bridge based on a difference in amplitude of a vibration component specific to the resonant bridge;
A method for detecting resonance in a bridge, comprising: A bridge resonance detection device that detects resonance of a bridge over which a moving object moves, comprising:
a resonance detection unit that detects N-th order resonance (N is an integer of 2 or more) of a short-span bridge having a span length shorter than the vehicle length of the vehicles that make up the moving body , based on the vertical vibration acceleration of the moving body measured from the moving body side;
A bridge resonance detection device characterized by the above. The bridge resonance detection device according to claim 11,
the resonance detection unit detects resonance of the short-span bridge based on a measurement result of an acceleration measuring device that measures vertical vibration acceleration of the moving body from the moving body side;
A bridge resonance detection device characterized by the above. The method for detecting resonance of a bridge according to claim 11,
the resonance detection unit detects resonance of the short-span bridge based on a measurement result of a passage displacement measuring device that measures a passage displacement on the bridge from the moving object side;
A bridge resonance detection device characterized by the above. A bridge resonance detection program for detecting resonance of a bridge over which a moving object moves, comprising:
A resonance detection procedure is executed by a computer to detect N-th order resonance (N is an integer of 2 or more) of a short-span bridge having a span length shorter than the vehicle length of the vehicles that make up the moving body, based on the vertical vibration acceleration of the moving body measured from the moving body side;
A bridge resonance detection program featuring: The bridge resonance detection program according to claim 14,
the resonance detection step includes a step of detecting resonance of the short-span bridge based on a measurement result of an acceleration measuring device that measures vertical vibration acceleration of the moving body from the moving body side;
A bridge resonance detection program featuring: The bridge resonance detection program according to claim 14,
the resonance detection step includes a step of detecting resonance of the short-span bridge based on a measurement result of a passage displacement measuring device that measures a passage displacement on the bridge from the moving object side;
A bridge resonance detection program featuring:

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